Background
Shape memory alloy belongs to a class of shape memory materials. It has ability to memorize and retain previous from the time to being subjected in order to specific stimulus like thermo-mechanical as well as magnetic variations. In addition, shape memory alloy has brought important attention as well as interest in current years in broad range of commercial applications for unique as well as superior properties (Clare et al. 2008). On the other hand, commercial development is supported through fundamental as well as applied research studies. The paper explains the attributes of shape memory alloys, which can make them suited to the actuators in several applications. Moreover, it identifies limitations for clarifying the challenges in design that are faced by the developers of shape memory alloys. The research provides a comprehensive literature review of current published journals, which are categorized against the related commercial domains as well as rated as per the design objectives of relevance on the domains such as automotive, aerospace, biomedical as well as robotic (Elahinia et al. 2012). Even though the research presents extensive review of shape memory alloys, different categories of shape memory alloys are discussed that includes historical overview, summary of current advancements as well as new application scopes.
The research aims to identify potential research areas for future development in application of shape memory alloys through conducting a comprehensive literature review.
Overview of shape memory alloy
Shape memory alloy are interesting materials with extraordinary properties, for example, shape memory impact and super versatility. These properties make them extremely intriguing for applications in various fields of science and designing. A higher quality and dependability in mix with a noteworthy diminishing in cost has made SMAs more typical. Subsequently, SMAs have passed their introductionary state and are presently getting a charge out of a critical development. They are a vital piece of the improvement of shrewd materials (Habijan et al. 2013). There are three principle sorts of business SMAs: CU-based combinations, Fe based compounds and Ni-Ti composites. Since Ni-Ti combinations are better analyzed than alternate SMAs for most business applications, particularly in the application part, concentrate basically on these alloys. This content comprise of three primary parts. The principal area incorporates an exhaustive depiction of the martensitic stage change, the premise of the shape memory impact and super elasticity. The second segment concentrates on the diverse strides of the conventional manufacture strategy for Ni-Ti SMAs. In the last area we depict agent SMA applications from a wide range of fields, keeping in mind the end goal to demonstrate the assorted variety and conceivable outcomes these materials speak to.
Shape memory alloy is a one of a class of metal combinations, which recuperate obvious changeless strains when it is warmed over a particular temperature. The shape memory compounds include two stable stages such as high temperature stage, called austenite as well as the low temperature stage, which is called martensite named after German metallographer. The key normal for all shape memory alloy is the event of a martensitic stage change which is a stage change between two strong stages and includes improvement of molecules inside the precious stone grid (Bormann et al. 2012). The martensitic change is related with inelastic issuesof the precious stone cross section with no diffusive procedure included. The stage change comes about because of an agreeable and aggregate movement of molecules on separations littler than the grid parameters. Martensite plates can develop at speeds which approach that of sound in the metal up to 1100m/s. Together with certainty, that martensitic change can happen at low temperatures where nuclear versatility might be little, brings about the nonattendance of dispersion in the martensitic change inside the time size of change. The nonappearance of dissemination makes the martensitic stage change practically momentary a first-arrange progress (Haberland et al. 2012). At the point when a shape memory alloy experiences a martensitic stage change, it changes from high symmetry typically cubic austenitic stage to low symmetry martensitic stage profoundly twinned monoclinic structure. NiTiNOL’s high temperature stage has B2 precious stone structure and its low temperature stage has B19′ gem structure. In the event that one overlooks the contrast amongst Ni and Ti particles, B2 precious stone structure is basically body– focused cubic and B19 has an indistinguishable symmetry from hexagonal– close pressed, aside from that the two types of molecules break hexagonal symmetry making the structure to tetragonal. B19′ is a little bending from B19. Thus, it is important to develop the process effectively so that the outcome of the procedure generates expected benefits.
Industry applications of shape memory alloy
Although medicinal applications for shape memory compounds (SMA) now overwhelm in the present market, there are numerous applications in the mechanical area which have achieved huge volume creation that far outperform the material use in the restorative fields. In the early development of shape memory alloy innovation the most vital applications were for latches and couplings, fundamentally in the military segment. With the developing of the innovation, and the more extensive accessibility of alloys, mechanical applications show up in a wide range of business. Eyeglass outlines were an early case of another utilization of super elasticity which has become an overall item. PDA receiving wires expend a huge number of feet of super elastic wire, and the advancement of underwire for ladies’ brassieres, in the past restricted to Asian market, is presently venturing into an overall design. Another thought of utilizing super elastic NiTi powder to implement the protection of SnPdAg weld against disappointment actuated by warm stress level seems promising (Shishkovsky et al. 2012). In the car area, European auto makers have for quite some time been utilizing SMA actuators for transmission liquid control. Presently, it is developing with the latest achievement in utilizing a NiTiNb plug for fixing high-weight fuel sections in diesel motor injectors. SMA actuators keep on achieving consistent development in security valves for both shopper and modern applications. New actuator applications incorporate a warm interrupter for shielding lithium particle battery from wild warm runaway (Haberland et al. 2013). Innovative work exercises proceed in vibration and damping standards. Utilizing either inactive or dynamic means are well demonstrated yet the commercialization has been ease back to create. Dynamic tuning of reverberation recurrence and seismic vibration controls may discover their specialties sooner rather than later. Small scale electromechanical (MEM) gadgets created utilizing dainty film NiTi actuators will likewise be quickly examined.
Among the different standards of SMA application, super elastic gadgets are the most noteworthy in both material utilization and business esteem. Today, NiTi SMA has accomplished a changeless place in high-end eyeglass outlines (Zhang et al. 2013). The utilization of superelastic SMA segments for the nose piece extension and ear pieces sanctuaries give enhanced wearer comfort and in addition awesome protection from unplanned harm. To accomplish the exceedingly wrinkle safe super elasticity over an extensive variety of ecological temperatures, these segments are generally profoundly chilly worked took after by a low temperature warm treatment to bestow work-solidified pseudo elasticity (Dadbakhsh et al. 2014). As a result of the trouble in welding NiTi to different materials, the closures of a NiTi connect are mechanically pleated into a silver-nickel packaging before being fastened onto the edges. NiTi outlines are currently made worldwide in the many plans with a wide assortment in surface complete and covering managed by form the mobile phone is presently pervasive being in see in practically every open field. The PDA receiving wire, some time ago of stainless steel, is currently all around fabricated from super elastic NiTi alloy because of incredible protection from changeless set on bowing and inadvertent harm (Haberland et al. 2014). Using a similar guideline for assembling super elastic NiTi eyeglass outline, huge frosty work is frequently used to upgrade the low temperature super elasticity.
Ni-rich science or ternary expansion is likewise used to accomplish this coveted property. Ladies’ brassieres have both stylish and in addition auxiliary necessities. The utilization of super elastic NiTi alloy to the wire re-requirement, called the underwire, was first created in Japan and is presently a critical worldwide market for SMA (Walker et al. 2014). NiTi underwire offer enhanced solace because of the much lower versatile modulus than the regular steel wires. An extra favorable position is the way that the super elastic NiTi wires are protection from lasting twisting which can be the aftereffect of washing and drying cycles. Various sizes and shapes are presently accessible offering an extensive variety of firmness and plan alternatives.
A later advancement uses the superelastic properties of NiTi powder to improve the protection of SnPbAg bind to warm weakness. As semiconductor circuits end up noticeably littler and all the more thickly pressed the need to control warm develop increments. Ordinary weld for joining electronic gadgets onto printed circuit sheets (PCB) regularly splits and delights when subjected to huge stress level actuated by the distinction in warm development coefficients between the part and the PCB (Bormann et al. 2014). Keeping in mind the end goal to get a valuable scattering of the little NiTi particles in the PbSnAg bind, the NiTi particles are covered with Cu by an electro less method preceding being fused in the weld network. Cu-covered NiTi powder implemented SnPbAg weld demonstrates enhancements in both firmness and pliability without noteworthy changes in electrical conductivity when contrasted with the solid SnPbAg patch. An alternative procedure is to generate NiTi shape memory alloys utilizing high density graphite crucibles in order to minimize carbon contamination of melt.
An exemplary case for the obliged recuperation applications is Cryofit coupling. The empty chamber of cryogenic NiTiFe combination has an inside measurement littler than the tubing breadth is first extended and put away in the martensitic state until get together (Mazzer et al. 2014). In the wake of introducing the extended coupling onto the tubing, the inward breadth of the coupling recoups its unique measurement and structures a solid joint with the tubing when the temperature warms to the ecological temperature. These couplings have been effectively utilized essentially to join water driven frameworks in military air ships with a little volume used in oil, petrochemical and utility enterprises.
Figure 1: SMA phases and structures
(Source: Gustman et al. 2016, p.625)
The appearance of the wide hysteresis NiTiNb compound has enormously expanded the degree for coupling and latches empowering these gadgets to be additionally prepared, put away, and transported in their twisted state at surrounding temperatures. Gadgets of wide hysteresis NiTiNb compound are warmed to recapture their unique shapes (Dadbakhsh et al. 2016). These ring gadgets now discover use in an expansive scope of electronic and mechanical gadgets, for example, connectors, fixing gadgets and bracing parts and give solid operation over a temperature run from 65°C to 300°C. A photo of Tinel Lock rings for joining protecting mesh onto electrical connectors (Gargarella et al. 2015). The latest achievement is the warmth to-recoup NiTiNb plug for fixing high-weight fuel entry in diesel fuel injectors. A normal overwhelming obligation diesel fuel injector involves a solenoid control valve, a plunger barrel and a fuel section connecting the initial two components. Through this entry a fuel correspondence is set up where the fuel is conveyed into the plunger chamber by means of control valve (Hagemann et al. 2015). The plunger pressurizes the fuel in abundance of 32,000 psi and the high-weight fuel is infused through shower spout into motor ignition chamber. Amid assembling, this fuel entry is bored from the outside of injector body, making an open end that requires fixing toward the finish of the assembling procedure. Regular fixing technique using a brazed steel plug frequently flops under delayed introduction to extraordinary recurrent weights. Other fixing technique using a warmth to-recoup NiTiNb plug offers a more dependable seal and can be introduced at much lower temperatures than a brazed steel plug. These NiTiNb fixing plug are made from bars that are longitudinally extended to have a diminished distance across. The extended bar is then sliced and ground to a completed width of high accuracy (Speirs et al. 2017). Amid establishment, the connection is embedded to the open end of fuel entry and warmth is connected to instigate shape recuperation of the NiTiNb plug (Dadbakhsh et al. 2015). Stress produced from compelled recuperation accordingly makes a tight seal around the tube shaped surface equipped for withstanding outrageous repetitive weights.
Shape memory alloy contains collection of metallic materials with proper capacity in order to recuperate characterized length or shape when it is subjected to appropriate mechanical stacks. The remarkable properties of SMA are promoted in several types of applications in distinctive fields of human knowledge. In the particular section, bio-medical applications of SMA are discussed. Cardiovascular application is one of the major applications in this. New generation devices are generally used for blood vessel interruption to prevent pulmonary embolism. The conventional surgery that fixes this oddity is amazingly obtrusive and risky. The thorax of the patient is opened and the atrial hole is sewn. As a result of the inherent dangers of this surgery, a few issues may happen. The atrial septal impediment gadget is a contrasting option to this surgery. This gadget is made out of SMA wires and a waterproof film of polyurethane. Similar to the case for the Simon channel, the surgery to put this gadget abuses the shape memory impact, being considerably less obtrusive than the conventional one. Initial, one portion of the gadget is embedded through a catheter by the vena cava up to the heart, in its shut shape. At that point, it is set on the atrial gap and opened, recouping its unique shape. Next, the second 50% of the gadget is put by an indistinguishable course from the first, and afterward the two parts are associated. This system seals the gap, dodging blood spill out of one chamber to the next. It is normal that the gadget will remain in the heart for an inconclusive timeframe since the heart tissue recovers.
On the other hand, self-growing stents, named after the dental practitioner C.T. Stent, are another vital cardiovascular application that is utilized to keep up the internal breadth of a vein. All things considered, these gadgets are utilized as a part of a few circumstances with a specific end goal to help any tubular entry, for example, the throat and bile pipe, and veins, for example, the coronary, iliac, carotid, aorta and femoral supply routes. In this sort of use, a round and hollow platform with shape memory is put, for instance, inside a vein through a catheter. At first, this framework is pre-compacted in its martensitic state. As the framework is warmed, because of the body temperature, it has a tendency to recuperate its unique shape, growing itself. This gadget can be utilized not just in the angioplasty method, with a specific end goal to keep another hindrance of a vessel, yet additionally in the treatment of aneurysms for the help of a debilitated vessel. Orthopedic applications SMA have an expansive number of orthopedic applications. The spinal vertebra spacer is one.
The inclusion of this space between two vertebrae guarantees the neighborhood support of the spinal vertebrae, keeping any awful movement amid the recuperating procedure. The utilization of a shape memory spacer grants the use of a consistent load paying little mind to the position of the patient, who protects some level of movement. Medicinal utilizations of shape memory compounds gadget is utilized as a part of the treatment of scoliosis.. On the left side, the spacer is in the martensitic state, and on the correct side, the spacer is in its unique shape, recuperated by the pseudoelastic marvel. Another application in the orthopedic region is identified with the recuperating procedure of broken and cracked bones. A few sorts of shape memory orthopedic staples are utilized to quicken the recuperating procedure of bone breaks, abusing the shape memory impact. The shape memory staple, in its opened shape, is set at the site where one wants to modify the broken bone. Through warming, this staple tends to close, compacting the isolated piece of bones is processed. It ought to be called attention to that an outer gadget plays out this warming, and not the temperature of the body. The power created by this procedure quickens recuperating, diminishing the season of recuperation.
Today, these applications are being created in various fields of science and designing. Essentially, SMA show two very much characterized crystallographic stages, like, austenite and martensite (Gustmann et al. 2016). Martensite is a stage that, without stretch, is steady just at low temperatures; what’s more, it can be instigated by either stress or temperature. Martensite is effortlessly distorted, achieving huge strains. As a result, there is a crystallographic introduction, lined up with the stress level heading, which is called detained martensite.
Austenite stage is steady just at high temperatures, having a solitary variation with a body-focused cubic precious stone structure (Evirgen et al. 2014). Martensitic change clarifies the shape recuperation in SMA. This change happens inside a scope of temperatures which fluctuates as indicated by the substance of each combination (Straka et al. 2014). Late examinations have demonstrated that, contingent upon particular conditions; some SMA can display another crystallographic stage known as R-stage. The R-stage change can show up before the martensitic change as indicated by the accompanying grouping: austenite → R-stage → martensite.
On account of their wonderful properties, SMA can be utilized as a part of countless applications. SMA can tackle issues in the avionic business, particularly those identified with vibration control of thin structures and sun oriented boards, and non-explosive discharge gadgets (Benafan et al. 2013). Micromanipulators and automated actuators have been utilized so as to mirror the smooth development of human muscles.
The designers have kept on using both the shape memory and pseudo elastic impacts of SMAs in taking care of designing issues in the aeronautic trade. Such executions of SMA innovation have spread over the regions of settled wing flying machine, rotorcraft, and rocket; work proceeds in every one of the three of these regions (Dehkord et al. 2017).
Figure 2: Use of shape memory alloy
(Source: Dehkordi et al. 2016, p.622)
The accompanying area depicts a portion of the all the more as of late investigated aviation uses of SMAs and after that quickly outlines the difficulties confronting the planners of such frameworks (Farhat et al. 2016). The undertaking was part into two stages with the first being the most SMA-serious.
Figure 3: View of SMA
(Source: Dehkordi et al. 2016, p.511)
Space applications are those which look to address the one of kind issues of discharge, activation, and vibration relief amid either the dispatch of a shuttle or its consequent operation in microgravity and zero air situations. Although activated structures in space are liable to low gravitational powers which diminish required actuator control, warm exchange can rapidly wind up plainly tricky on account of the absence of a convective medium. It ought to be noticed that for most outlines portrayed underneath, almost no demonstrating of the SMA conduct was performed. Frameworks were outlined through watchful experimentation. Maybe the most productive utilization of SMAs in space is in taking care of the issue of low-stun discharge. These gadgets are very famous in the outline of rocket, and have been being developed for quite a while. It has been assessed that, up to 1984, there are 14 for each penny of room missions encountered some kind of stun disappointments, half of these making the mission be prematurely ended. Pyrotechnic discharge systems were regularly observed to be the underlying driver. Since they can be activated gradually by slow warming, SMA segments are suited for use in low-stun discharge instruments and have been presented for use on both normal measured and littler ‘small scale’- estimated satellites. The approach of these littler satellites has made a requirement for more reduced discharge gadgets which are a request of greatness littler than their off-the-rack partners. Examination concerning this one of a kind issue has prompted gadgets which are right now accessible, including the prevalent Qwknut. Other, substantially littler gadgets which utilize SMA components for activation have additionally been proposed, for example, the Micro Sep-Nut. In both of these gadgets, the straightforward SME is utilized. The dynamic parts twisted and detwinned before establishment. In circle, the component is then warmed, shape is recuperated, and discharge happens. Rehashed utilize instruments, for example, the turning lock have additionally been presented. Considerably littler rotational actuators are being produced through miniaturized scale creation techniques, for example, shape affidavit fabricating and electroplating. Utilizing these techniques, it was shown that revolving actuators could be developed with a most extreme measurement of 5 mm; however give an incitation point of 90?. Each of these little discharge gadgets exhibits the versatility of outlining with SMA parts. To give a similar minimized activation with customary strategies would require that little moving parts be manufactured. Dynamic SMA Components, then again, are on an indistinguishable size scale from the actuator lodging itself. Another SMA application is the incitation of different shuttle parts by means of SME. One early case incorporates a SMA-incited sun based gatherer using tensional components which can change its shape to streamline execution. In a minor departure from this thought, another satellite used a SMA wire-incited stepper engine for introduction of its sun powered folds. For a comparable reason, the lightweight adaptable sunlight based exhibit (LFSA) and the shape memory composite warm fitting analysis (SMATTE) were created. The LFSA consolidated a thin SMA strip at the pivot area which, when warmed and incited, opened a formerly collapsed sun oriented exhibit. Sending has been appeared to take roughly 30 s. This work was a community oriented exertion between Lockheed Martin and NASA-Goddard. The SMATTE is a proof-of-idea try demonstrating that a board could be distorted starting with one stable shape then onto the next by means of activation of a SMA thwart connected to just a single surface of the board. Such an outline could be utilized to tailor the state of rocket radio wires (Farhat et al. 2016). Another case of potential basic transforming is the hostile flexural unit cell talked about before in reference to settled wing flying machine. An alternate and surely understood SMA space incitation use of SMAs is the Mars Pathfinder mission in 1997.
The mission incorporated a SMA actuator which served to pivot a tidy cover from a particular district of a sunlight based cell with the goal that the power yield of this ensured and clean area could be contrasted with the power yield of non-secured locales, subsequently evaluating the negative impacts of tidy settling on the sun based boards. At long last, specialists have researched utilizing SMA strips to help inflatable structures for use in space. This fascinating application can use both the shape memory and pseudo versatile impacts. The incitation of SME is utilized to help send the structure, while the substantial yet completely recoverable disfigurements gave amid pseudo flexible stacking help save its shape. Limited component execution of a three-dimensional SMA constitutive model was utilized to demonstrate this framework and it was demonstrated that such actuated strips can keep up a given surface design of an inflatable structure. In any case, issues exist in utilizing a generally thick SMA strip joined to a thin inflatable layer; it is normal that a thin-film SMA may yield far and away superior outcomes.
SMAs have likewise been utilized as sensors. On account of detecting, SMAs are utilized to get data from a thermo mechanical framework. This is conceivable due to the material property changes which happen amid the stage change actuated amid warming or stacking (Shahverdi et al. 2016). For instance, each stage has its own particular electrical resistivity, which can be checked to demonstrate when a SMA component is encountering a stage change actuated by stretch which is itself incited by distortion. An early case of a space application idea used capacity of a SMA to go about as a sensor in observing the redirection of expansive traverse space structures.
In spite of the fact that they are not entirely direct, the general slant of the change lines in stress– temperature space is regularly alluded to as the stress level rate or the stress level impact coefficient. In order to enable an investigator or architect to recognize which stage is available at a given thermo mechanical express, a stage outline is developed, which shows the stress level reliance of the martensitic change temperatures (Baro et al. 2014). Some particular parcels of the stage chart demonstrate where stages are relied upon to exist in unadulterated frame, and different areas show where change starting with one stage then onto the next will happen and where at least two stages can exist together. Review yet again that these change limits are not really straight and are just spoken to thusly for this schematic outline. A more enlightening introduction of these changes locales and their discretionary portrayals can be found in the writing. The stress level pivot speaks to a uniaxial part of stress or, when all is said in done, some scalar measure of stress.
SMAs include in two different stages with three different types of precious stone structures such as twinned martensite, austenite as well as detwinned martensite. There are six conceivable changes in the process. The austenite structure is properly steady at high temperature along with the martensite structure that is steady at bringing down temperatures. However, on the other hand, when a SMA is warmed, it is getting started to change from martensite into the austenite stage. On the other hand, the austenite-begin temperature (As) is where this change begins as well as austenite-complete temperature (Af) changes is finished (Silva et al. 2012). Once a SMA is warmed past as it contracts and changes into the austenite structure, i.e. to recoup into its unique shape. This change is conceivable even under high connected burdens, and in this manner, brings about high activation vitality densities. Amid the cooling procedure, the change begins to return to martensite at martensitestart-temperature (Ms). In any case, TWSMA is less connected financially due to the ‘preparation’ prerequisites and to the way that it for the most part creates about portion of the recuperation strain gave by OWSMA to a similar material and it strain has a tendency to break down rapidly, particularly at high temperature (Bhatt et al. 2016). Consequently, OWSMA gives more solid and temperate arrangement. Different preparing techniques have been proposed, and two of them are: Spontaneous and outer load-helped acceptance. (3) Pseudoelasticity (PE) or Superelasticity (SE).
In addition, the ‘material TWSME’ over, a one-sided OWSMA actuator could likewise go about as a ‘mechanical TWSME’ at a naturally visible (auxiliary) level; which is all the more capable, solid and is broadly executed in many building applications (Sadrnezhaad et al. 2009). The SME is a diffusionless strong stage progress amongst martensitic and austenitic precious stone structures. There are different changes related with shape memory, for example, rhombohedral (R-stage), bainite and the ‘rubberlike conduct’ (RLB) in martensite arrange, which are not talked about in detail, in this work (Bormann et al. 2014). This property is critical and requires watchful thought amid SMA material choice for focused specialized applications; e.g. a little hysteresis is required for quick activation applications, (for example, MEMSs and mechanical autonomy), bigger hysteresis is required to hold the predefined shape inside an expansive temperature extend. Moreover, the progress temperatures alluded to recognize the working scope of an application (Biffi and Tuissi 2014). These change temperatures and the hysteresis circle conduct is affected by the organization of SMA material, the thermo-mechanical preparing custom fitted to the SMA and the workplace of the application itself. These progress temperatures can be straightforwardly measured with different systems, for example, differential checking calorimetry (DSC), dilatometry, electrical resistivity estimation as an element of temperature, and can be in a roundabout way decided from a progression of consistent stress level warm cycling tests.
In the 1990’s, the term shape memory technology (SMT) was brought into the SMM people group. SMA application configuration has changed from multiple points of view from that point forward and has discovered business application in a wide scope of ventures including car, aviation, apply autonomy and biomedical (Dilibal et al. 2017). At present, SMA actuators have been effectively connected in low recurrence vibration and incitation applications. In this way, much orderly and concentrated research work is as yet expected to improve the execution of SMAs, particularly to build their data transfer capacity, weakness life and strength. As of late, numerous scientists have adopted a test strategy to upgrade the characteristics of SMAs, by enhancing the material pieces evaluating the SMA stage progress temperature to accomplish a more extensive working temperature range, and better material strength, and in addition to enhance the material reaction and stroke with better mechanical outline, controller frameworks and creation forms (Malukhin and Ehmann 2006). Research into elective SMMs, structures or shapes, for example, MSMA, HTSMA, SMP, shape memory clay, SMM thin film or a mix of them are additionally seriously being led, and the quantity of business applications is developing every year. More points of interest of late applications and improvement of SMA are portrayed in the consequent areas.
Conventional method of manufacturing of shape memory alloys
In this segment, the conventional manufacture strategies for SMAs are examined. The succession in which the strategies are displayed matches a genuine finish creation process, with the assembling forms depicted last.
Casting
Most of the SMA items are thrown in a semi finished frame, as indicated by the expected application. The most widely recognized structures incorporate ingots, chunks, billets, strips, foils, poles, or wires. The coveted type of the cast item characterizes the throwing technique utilized. The previously mentioned shapes are fundamentally created through constant throwing strategies with fast cementing; for example, liquefy turning, planar stream throwing and twin-move throwing (Malukhin and Ehmann 2006). A little separation in the amount of each of the soften parts brings about an alternate SMA with extraordinary separation in its properties. Sometimes, the underlying throwing of the SMA might be trailed by a few reemits, all together for the subsequent material to introduce better homogeneity. Another incredible risk to the uprightness of the alloy is the presence of some tainting factors. Contaminants can enter the composite either in light of the low immaculateness of the first materials, or amid the throwing of the item. Utilizing part materials of high immaculateness can dispose of the main case. Keeping in mind the end goal to counteract conceivable defilement of the alloy amid its manufacture, both the dissolving and the throwing of the part materials are typically performed under a defensive domain, comprising of Ar or other honorable gas, or in a vacuum (Malukhin and Ehmann 2007). Different wellsprings of defiling components amid this progression are the pot utilized and the oxides framed amid the cementing. This makes the requirement for appropriate determination of a non-tainting pot, reasonable for the dissolve, to a great degree significant. Most of the time, the cauldron can be made out of graphite, calcia, alumina, magnesia, and other comparable material, with some being more appropriate than others, contingent upon the threw alloy (Priyadarshini et al. 2011). Aside from the defensive climate, with a specific end goal to keep the shaped oxides from tainting the fundamental volume of the last material, now and again water is flowed around the thrown material. The circled water builds the warmth spill out of the external surface of the material, making the oxides be shaped there, along these lines keeping up the virtue of the alloy while making the oxides less demanding to evacuate subsequently.
Defilements can have critical impacts in the nature of the last material. Much of the time, they cause noteworthy changes in the temperature levels of the last material, making its conduct erratic, or even contradictory for the expected applications. Additionally, because of the exceedingly receptive conduct of a few parts, dissolving forms in a vacuum are regularly fundamental (Oliveira et al. 2016). Some such normal procedures are vacuum acceptance liquefying and the vacuum consumable bend dissolving forms. At long last, a standout amongst the most vital strides of the throwing procedure in the manufacture of SMAs is the cementing of the dissolve.
Heat treatment
Heat testing alludes to an assortment of procedures through which the material microstructure is being modified. By means of the microstructure modification, numerous physical and concoction properties of the material change. For the SMAs, warm treatment forms show a critical part and are essential for the SME instrument to occur. A standout amongst the most surely understood warmth treating forms utilized amid the creation of a SMA includes the strengthening of the material directly after the throwing procedure. Contingent upon the throwing procedure, the microstructure of the SMA directly after the throwing procedure may introduce an absence of homogeneity (Bischoff et al. 2017). This influences a few of the mechanical and physical properties of the SMA.
A similar procedure is additionally connected after the material has been subjected to frosty assembling forms keeping in mind the end goal to diminish the leftover burdens incited. As said beforehand, the rehashed thermo-mechanical stacks cycles. Subsequently, strengthening of the material can return some of these perpetual miniaturized scale auxiliary changes, consequently reestablishing the shape memory conduct of the material (Meisel et al. 2015). Consideration is required, however, with the goal that the strengthening procedure won’t change the underlying properties of the SMA. The procedure includes the firm requirement of the material and the resulting warming at a specific temperature. From that point onward, a snappy douse in a cooling medium strongly characterizes the previously mentioned temperature level. The primary contrast amongst toughening and maturing lies in the length and the greatest temperature of each procedure. By and large, for a similar material, maturing is performed in bring down temperatures than the toughening, yet for an expanded timeframe. Regular strategies for warm change in warm treatment forms include a defensive environment or a vacuum heater, salt or sand showers, use of warmed bites the dust, and other warming techniques (Dudziak et al. 2010). At long last, basic techniques for limiting the SMA item before warm treating include the utilization of specific gadgets, for example, an apparatus, a mandrel, or others. Picking the privilege compelling gadget is vigorously influenced by the underlying structure given amid throwing, and also the warming gadget utilized.
Forming
After the heating treatment of the material, a few assembling forms are frequently used to accomplish the coveted item measurements. These assembling procedures can either be icy or hot. Although hot-worked items exhibit better conduct as far as their thermo-mechanical properties, once in a while cool assembling forms are required. As noted above, on the off chance that a SMA is fabricated by means of cool procedures, the material ought to be submitted a while later to toughening to diminish the work-solidifying. Besides, both in icy and in hot procedures, if the distortion is high, in respect to the item’s underlying measurements, the general misshapening is performed in different goes with a specific end goal to keep the likelihood of deformity development (Walker et al. 2016). Creator’s own duplicate assembling procedures of shape memory compounds. A SMA’s workability in distortion fabricating forms is exceptionally associated with the material’s pliability. A noteworthy issue that framing producing forms posture, as far as the material’s strain recuperation, rests with the fundamental instrument of these procedures. Amid a twisting procedure, the material is compelled to go through a specific opening, or to involve a specific volume. This technique gives distinctive introduction to the material grains, accordingly bringing about a microstructure with various grain introductions. As examined over, this marvel causes a reduction in the material’s strain recuperation, in this manner bringing about an exhausted SMA (Shiva et al. 2015). This is significantly more overwhelming in icy assembling forms, as amid a hot procedure the material is progressively recrystallized at the same time. Strengthening the material after a distortion producing procedure can change the introductions of the grains to more positive ones. As far as apparatuses and hardware, each assembling procedure presents distinctive necessities. The apparatuses are normally built of hard materials, as a great deal of the SMAs requires high loads so as to be disfigured.
Forging
Manufacturing is a framing procedure in which the metal is compelled to involve a given geometry. For the most part, the connected load is uniaxial. It is given by a press. On the other hand, the geometry which the material is compelled in order to possess is engraved in either of the kicks the bucket, as indicated by the producing sort (Yu et al. 2015). As a rule, this geometry is close to the coveted state of the material. Because of the idea of the assembling procedure, the vast majority of the material misshapes plastically, while a little level of the material distorts flexibly. In this way, keeping in mind the end goal to Author’s own duplicate 168 Materials Forming and Machining accomplish the correct measurements of the last item, the kicks the bucket are outlined undersized or on the other hand, the item may continue to a machining fabricating process, so as to be framed in the coveted measurements. Producing is a typical procedure for the assembling of SMA ingots or billets. As specified above, because of the way that the SMA needs to stream in specific ways to involve the given geometry of the passes on, the subsequent material will give a microstructure fluctuating introductions (Walker et al. 2014). With a specific end goal to diminish this marvel, fashioning is normally executed (Dadbakhsh et al. 2016). If there should arise an occurrence of icy manufacturing, the material’s strain rate is higher, causing more unsteady distortions. With a specific end goal to secure a higher quality SMA, visit between pass tempering is viewed as imperative.
Rolling
Rolling is an assembling procedure in which the material is getting compelled in order to go between two conversely pivoting rolls. The two rolls need to turn with a similar outright spiral sustain speed brings about a more slender white layer. The white layer framed in an EDM handled work piece with two diverse cutting parameters is watched. The white layer shaped in EDM is more slender than that of processing. Besides, for complete trim cut, the white layer is much more slender and breaks free. Material evacuation rate likewise increments with increment in working vitality. Comparable outcomes are accounted for when WEDM is viewed as; surface harshness and material evacuation rate increment with an expansion in machining vitality. The parameters of WEDM are Fe-based SMAs (Kho et al. 2016). They have measured a noteworthy increment of the workpiece’s hardness close to the external surface because of the development of a recast layer. The recast layer is additionally in charge of a debasement of the shape recuperation of the analyzed SMAs.
SLM:
The NiTi powder utilized as a part of this paper has a normal nuclear level of 49.91% Ni and 50.09% Ti. The powder was delivered by gas atomization of NiTi ingot with a molecule estimate going from 20 to 50 μm. To create the NiTi tests with measurements of 5 mm by 5 mm under the argon climate, a modified SLM machine was utilized. A thick layer of powder was stored on the highest point of the aluminum base plate amid the manufacture procedure and just the best layer of the powder bed will be dissolved and cement when the laser examined over the powder bed (Otubo et al. 2003). There will in any case be a layer of powder underneath the set layer and the examples won’t be in contact with the base plate. This technique not just keeps the sullying of tests because of the conceivable response between the base plate and NiTi SMA, it makes the evacuation of tests considerably simpler also. By the by, the specimens created in this paper just comprised of a solitary set layer. In this way, the examples delivered here are thought to be 2D. With respect to the procedure parameters, the laser power and laser checking speed were been the variable parameters while whatever is left of the parameters were kept steady.
Figure 3: Shape memory alloy by SLM
(Source: Shiva et al. 2015 p.514)
Visual assessments were first utilized to limit the vast number of tests required for thickness estimation. The essential criteria utilized as a part of visual examinations are that the examples must have obvious liquefying of powder, great dimensional precision and least oxidation. There are few specimens with poor softening, poor dimensional exactness and oxidation issue (Shiva et al. 2015). It likewise introduces a case of a decent specimen for correlation. The specimens chose after visual examinations were then subjected to the estimation of their mass densities, relative densities and shut porosities. In light of these outcomes, the specimens that were created with a laser energy of 50 to 60 W. The laser checking rate of 3100 to 4000 mm/s have the most astounding and most reliable readings of mass and relative densities. At the end of the day, these examples will have the most reduced shut porosities and they were experienced further testing for the nearness of stage change.
LENS
An extensive variety of biomaterials, including metals, polymers, pottery as well as composites are utilized as orthopedic inserts for substitutions or repairs of hard tissues, each with its own particular benefits and confinements (Krishna et al. 2009). Among the different biomaterials accessible for the specialists, NiTi shape memory combination is especially appealing a direct result of its one of a kind thermo mechanical properties, to be specific shape memory impact and super versatility. The super versatile property of NiTi is very like that of the human tissues, for example, ligament and bones. The similitude in stress– strain reaction enormously diminishes the level of stress protecting in orthopedic applications and subsequently decreases bone misfortune in the influenced range.
Figure 4: Shape memory alloy in LENS
(Source: Babacan et al. 2017, p.352)
Also, the nearness of a thin and normally shaped TiO2 film on NiTi grants to it genuinely great consumption protection and biocompatibility. While considering the appropriateness of a metallic material for orthopedic embed, either as bone substitution or in bone obsession, two practices are especially vital (Man et al. 2005). The first is the osteointegrating ability of the embed which ensures satisfactory holding quality amongst embed and bone. The second one is the measure of unsafe metallic particles discharged from the embed. A typical strategy to advance osteointegration of NiTi inserts is accomplished by covering NiTi with hydroxyapatite (HA). Despite the fact that bioactive, HA is an earthenware and does not bond emphatically to metals (Meisner et al. 2015). As of late, the advancement of mass permeable NiTi to advance osteointegration by encouraging cell bond, relocation, development and expansion has been accounted for. The strategies utilized to create mass permeable NiTi incorporate hot isostatic squeeze (HIP), ordinary sintering and self-engendering high-temperature blend (SHS). While mass permeable NiTi tests have appealing properties, they may not be sufficiently solid for huge load-bearing applications. Indeed, the quality of permeable NiTi diminishes straightly with the expansion of porosity (Elahinia et al. 2017). The erosion protection of permeable NiTi likewise diminishes with the expansion of porosity. Laser surface adjustment of NiTi to upgrade consumption protection going for decreasing Ni particle discharge has been endeavored by our gathering as of late. As a further advance in enhancing the biocompatibility of NiTi as orthopedic inserts, the present investigation utilizes laser treatment to mass NiTi tests with a permeable surface layer to improve osteointegration and to decrease the measure of Ni.
EBM
The shape memory alloy manufacturing process through unusual process in order to generate NiTi shape memory is through vaccum induction melting by utilzing a graphite crucible that casues contimation of melt with carbon. On the other hand, contamination with oxygen is originated from residual oxygene inside the chambar of melting. In addition, it is important to generate NiTi alloys is through electron beam melting (Man et al. 2005). It is using water cooled copper crucible, which can eliminate carbon contamination. The oxygen contaminaation would be very minmal for operation in a vaccum. Present work presents the outcome on the scale up porgram that includes chemical composition homogenity and in terms of carbon contamination. The commercially generated VIM genetrated VIM products and on the starting of raw materials.
DMD
Shape memory alloys are materials that show specific mechanical and warm reactions: the supposed super versatility condition when huge recoverable strains up to 8.5% exist at a consistent temperature and the SMAs display elastic like conduct and the shape memory impact SME when SMAs can completely recoup the obviously plastic strains with incredible power because of the austenite-martensite change. Such conduct is much of the time alluded to as “pseudoplasticity.” As an outcome, SMAs can create to great degree substantial microstrains on the request of 104 or proportionately 10% strain (Yu et al. 2015). This property of the material can be utilized as a part of joint less solid structures for incitation and control purposes with high power yield in an obliged space, e.g., in micro factories. The change temperatures TTRs are one of the key parameters for SMA based activation. TTRs are the essential for the material to display the SME. They likewise characterize the correct application for a specific NiTi piece combination restorative and mechanical (Elahinia et al. 2017). Traditionally, SMAs are made by high-recurrence enlistment, argon circular segment, plasma curve, or electron bar liquefying. Softening is played out a few times in succession to guarantee the homogeneity of the made material. Softening is trailed by hot/chilly working and warm treatment tempering and extinguishing. Otsuka and Ren arranged NiTi amalgams utilizing their Ni content as a marker of their execution extend. Utilizing a Landay-sort show, they express that the higher the versatile modulus bigger measure of Ni of the material the lower the TTRs are. Along these lines, the impact of extinguishing, which expands point surrenders, is equal to a compositional change flexible modulus increment (Kho et al. 2016). Since the versatile modulus can be dealt with as an impact caused by creation, the two terms are utilized as equivalent words in the paper (Elahinia et al. 2017). Henceforth, extinguishing brings down the TTR, since it builds the versatile modulus of the material. For instance, nuclear percent structure change of Ni content give or take can bring about a roughly 10% change in versatile modulus less or in addition to in like manner and decline or increment of the TTR by as much as a few many degrees.
Alternate factors that influence the arrangement of SMAs and, in this way, their Ni content are the level of polluting influences amid the creation procedure and the level of precipitation in the SMA material. On account of debasements, the most imperative truth to consider is the high reactivity of Ti with oxygen at high temperature levels. Encourages extra stable stages, for example, NiTi2 and Ni3Ti as per the NiTi stage outline display in the NiTi amalgam don’t show the SME, yet their quality modifies the compound organization, and consequently influences the TTRs. Metastable hastens Ni4Ti3 at last changing into Ni3Ti encourages intervene martensite change (Saedi et al. 2017). This conclusion originated from the way that the creators did not accomplish any TTRs in strong arrangement treated NiTi tests, yet acquired the TTRs in precipitation-solidified specimens. For this situation, strong arrangement was utilized to accomplish better homogeneity of the material. At long last, it created the impression that with an expansion in Ni content in the NiTi compound the martensitic temperature diminished straightly. This trademark permits the utilization of the amalgams in restorative, organic, and different applications that require low incitation temperatures.
This takes out any probability of tainting of the powder by the cauldron itself. This procedure takes into consideration the making of exceptionally unadulterated and circular powders, free of fired polluting influences related with cauldron based framework, and with greatly low oxygen substance (Wang et al. 2016). To limit other debasement substance, the whole procedure is directed under a latent air of argon gas. To think about the warm and useful properties of SLM NiTi, round and hollow bars were produced in the vertical heading. Stage change was assessed utilizing a Perkin Elmer Diamond DSC as indicated by ASTM F2004-05. The warming and cooling rate was set to 10 K/min (Wan et al. 2017). A 0.5 mm cut was expelled from the focal point of the round and hollow examples for DSC investigation. These stress level esteems were picked in light of the fact that they relate to imperative focuses along the stress level strain bend.
SLS
The Selective Laser Sintering in additive manufacturing is the laser-based technique using solid powders like plastics. The laser beam controlled by computers bids the particles together in the powder bed through increasing the powder temperature over the glass transition point. The technology has been appropriate for the moving parts, living hinges, interlocking parts and the other complex designs. It serves its activities in fully functional prototypes or the series of the complicated end-use sections.
It’s ideal applications lie in the prototypes with the mechanical properties against the injection-molded sections (Bhatt et al. 2016). This includes the series of smaller components as the cheaper alternative to the injection molding. The technology is also useful in personalized manufacturing, economic production of the complex and unique designs developed as the one-off products or under small batches. It is also applicable to the lightweight designs through utilizing the complicated lattice structures.
Polyjet method
The Polyjet is perfect to reproduce the prototype models. Its parts never need any support structure. It is best suited for the detailed and accurate applications. Various materials are available like the dual blend, rubber, rigid and clear materials to over mold the applications. The Polyjet printing is a fast process of prototyping using the additive manufacturing (Salmi et al. 2013).
The printers comprises of jetting heads spraying the boundaries of the parts according to layers. Here the liquids used are the photopolymers. This gets cured instantly by the UV lamp under the printer. This creates the plastic like solid model which is accurate and precise. A gel like substance is used as the supporting material that is washed away easily. Ultimately the model possesses a smooth finishing (Farhat et al. 2016). Thus it gets ready for tapping, drilling, painting and sanding.
The commercial and research interest for SMMs, especially in SMAs are quickly expanding, and numerous potential new applications have been proposed. The shot of achievement of another thought can be assessed and positioned into three unique classifications of uses, i.e. substitution, rearrangements and novel applications. Applications with higher curiosity and great aggressive cost are all the more fascinating and have a superior opportunity to infiltrate the market. A couple of effective mass created SMA applications in the market are the underwire brassiere, the cell phone radio wire, eyeglass outlines, the SMA pneumatic valves created by Alfmeier Präzision AG for the lumbar help gadget in auto seats. In any case, the rates of industrially fruitful SMA applications are as yet thought to be low. The future trends in SMAs can be normal at three distinct levels advancement of new or enhanced SMAs, mix of the practical properties of SMAs with the basic properties of different materials and look for new markets. The advancements of new or enhanced SMAs have fundamentally improved SMAs traits and exhibitions. Numerous scientists are as of late intrigued by ‘programming’ the SMMs by locally implanting different shape recollections into SMMs with different strategies to set the transitory shapes without forever changing the material properties, rather than using the conventional training method. In addition, there are generally three possibilities of melting as well as casting on nickel rich side.
Shape memory alloys (SMAs) have a place with a class of shape memory materials (SMMs), which can ‘remember’ or hold their past frame when subjected to certain jolt, for example, thermo mechanical or attractive varieties. SMAs have drawn critical consideration and enthusiasm for late years in a broad range of business applications, because of their one of a kind and unrivaled properties; this business improvement has been upheld by basic and connected research thinks about. This work portrays the properties of SMAs that make them preferably suited to actuators in different applications, and addresses their related confinements to illuminate the plan challenges looked by SMA designers. This work gives a convenient survey of late SMA research and business applications, with more than 100 cutting edge licenses; which are ordered against important business spaces and appraised by plan destinations of significance to these areas (especially car, aviation, automated and biomedical). In spite of the fact that this work shows a broad survey of SMAs, different classes of SMMs are additionally talked about; including a verifiable review, rundown of late advances and new application openings.
References
Andani, M.T., Saedi, S., Turabi, A.S., Karamooz, M.R., Haberland, C., Karaca, H.E. and Elahinia, M., 2017. Mechanical and shape memory properties of porous Ni 50.1 Ti 49.9 alloys manufactured by selective laser melting. Journal of the Mechanical Behavior of Biomedical Materials, 68, pp.224-231.
Antunes, A.S., Tosetti, J.P.V. and Otubo, J., 2013. High shape recovery Ni–Ti SMA wire produced from electron beam melted ingot. Journal of Alloys and Compounds, 577, pp.S265-S267.
Antunes, A.S., Tosetti, J.P.V. and Otubo, J., 2013. High shape recovery Ni–Ti SMA wire produced from electron beam melted ingot. Journal of Alloys and Compounds, 577, pp.S265-S267.
Antunes, A.S., Tosetti, J.P.V. and Otubo, J., 2013. High shape recovery Ni–Ti SMA wire produced from electron beam melted ingot. Journal of Alloys and Compounds, 577, pp.S265-S267.
Babacan, N., Atli, K.C., Turkbas, O.S., Karaman, I. and Kockar, B., 2017. The effect of dynamic aging on the cyclic stability of Cu73Al16Mn11 shape memory alloy. Materials Science and Engineering: A, 701, pp.352-358.
Baró, J., Martín-Olalla, J.M., Romero, F.J., Gallardo, M.C., Salje, E.K., Vives, E. and Planes, A., 2014. Avalanche correlations in the martensitic transition of a Cu–Zn–Al shape memory alloy: analysis of acoustic emission and calorimetry. Journal of Physics: Condensed Matter, 26(12), p.125401.
Benafan, O., Noebe, R.D., Padula, S.A., Garg, A., Clausen, B., Vogel, S. and Vaidyanathan, R., 2013. Temperature dependent deformation of the B2 austenite phase of a NiTi shape memory alloy. International Journal of Plasticity, 51, pp.103-121.
Bhatt, R.C., Meena, R.S., Kishan, H., Awana, V.P.S. and Agarwal, S.K., 2016. Structural, Magnetic, and Magnetocaloric Studies of Ni50Mn30Sn20 Shape Memory Alloy. Journal of Superconductivity and Novel Magnetism, 29(12), pp.3201-3206.
Biffi, C.A. and Tuissi, A., 2014. Fiber laser drilling of Ni 46 Mn 27 Ga 27 ferromagnetic shape memory alloy. Optics & Laser Technology, 63, pp.1-7.
Bischoff, A.J., Hua, K. and Mayr, S.G., 2017. Insights into growth of Fe7Pd3 ferromagnetic shape memory alloy thin films. Crystal Growth & Design, 17(5), pp.2374-2378.
Bormann, T., Müller, B., Schinhammer, M., Kessler, A., Thalmann, P. and de Wild, M., 2014. Microstructure of selective laser melted nickel–titanium. Materials Characterization, 94, pp.189-202.
Bormann, T., Schumacher, R., Müller, B., Mertmann, M. and de Wild, M., 2012. Tailoring selective laser melting process parameters for NiTi implants. Journal of Materials Engineering and Performance, 21(12), pp.2519-2524.
Bormann, T., Müller, B., Schinhammer, M., Kessler, A., Thalmann, P. and de Wild, M., 2014. Microstructure of selective laser melted nickel–titanium. Materials Characterization, 94, pp.189-202.
Clare, A.T., Chalker, P.R., Davies, S., Sutcliffe, C.J. and Tsopanos, S., 2008. Selective laser melting of high aspect ratio 3D nickel–titanium structures two way trained for MEMS applications. International Journal of Mechanics and Materials in Design, 4(2), pp.181-187.
Dadbakhsh, S., Vrancken, B., Kruth, J.P., Luyten, J. and Van Humbeeck, J., 2016. Texture and anisotropy in selective laser melting of NiTi alloy. Materials Science and Engineering: A, 650, pp.225-232.
Dadbakhsh, S., Speirs, M., Kruth, J.P. and Van Humbeeck, J., 2015. Influence of SLM on shape memory and compression behaviour of NiTi scaffolds. CIRP Annals-Manufacturing Technology, 64(1), pp.209-212.
Dadbakhsh, S., Speirs, M., Kruth, J.P., Schrooten, J., Luyten, J. and Van Humbeeck, J., 2014. Effect of SLM parameters on transformation temperatures of shape memory nickel titanium parts. Advanced Engineering Materials, 16(9), pp.1140-1146.
Dehkordi, M.B., Khalili, S.M.R. and Carrera, E., 2016. Non-linear transient dynamic analysis of sandwich plate with composite face-sheets embedded with shape memory alloy wires and flexible core-based on the mixed LW (layer-wise)/ESL (equivalent single layer) models. Composites Part B: Engineering, 87, pp.59-74.
Dilibal, S., Sahin, H., Dursun, E. and Engeberg, E.D., 2017. Nickel–titanium shape memory alloy-actuated thermal overload relay system design. Electrical Engineering, 99(3), pp.923-930.
Dudziak, S., Gieseke, M., Haferkamp, H., Barcikowski, S. and Kracht, D., 2010. Functionality of laser-sintered shape memory micro-actuators. Physics Procedia, 5, pp.607-615.
Elahinia, M.H., Hashemi, M., Tabesh, M. and Bhaduri, S.B., 2012. Manufacturing and processing of NiTi implants: a review. Progress in materials science, 57(5), pp.911-946.
Elahinia, M., Toker, G.P., Karaca, H., Benafan, O., Bigelow, G.S., Moghaddam, N.S., Amerinatanzi, A. and Saedi, S., 2017. Additive Manufacturing of NiTiHf High Temperature Shape Memory Alloy.
Evirgen, A., Karaman, I., Santamarta, R., Pons, J. and Noebe, R.D., 2014. Microstructural characterization and superelastic response of a Ni 50.3 Ti 29.7 Zr 20 high-temperature shape memory alloy. Scripta Materialia, 81, pp.12-15.
Farhat, H., Oguocha, I., Evitts, R. and Griffin, R., 2016, September. The Effect of the Novel FeNiCoAlTa Shape Memory Alloy Treatments on its Corrosion Behavior When Used as a Pipe Coupler. In Qatar Foundation Annual Research Conference Proceedings (Vol. 2016, No. 1, p. EEPP2826). Qatar: HBKU Press.
Gargarella, P., Kiminami, C.S., Mazzer, E.M., Cava, R.D., Basilio, L.A., Bolfarini, C., Botta, W.J., Eckert, J., Gustmann, T. and Pauly, S., 2015. Phase formation, thermal stability and mechanical properties of a Cu-Al-Ni-Mn shape memory alloy prepared by selective laser melting. Materials Research, 18, pp.35-38.
Gu, D. and He, B., 2016. Finite element simulation and experimental investigation of residual stresses in selective laser melted Ti–Ni shape memory alloy. Computational Materials Science, 117, pp.221-232.
Gustmann, T., Neves, A., Kühn, U., Gargarella, P., Kiminami, C.S., Bolfarini, C., Eckert, J. and Pauly, S., 2016. Influence of processing parameters on the fabrication of a Cu-Al-Ni-Mn shape-memory alloy by selective laser melting. Additive Manufacturing, 11, pp.23-31.
Haberland, C., Meier, H. and Frenzel, J., 2012, September. On the properties of Ni-rich NiTi shape memory parts produced by selective laser melting. In ASME 2012 Conference on Smart Materials, Adaptive Structures and Intelligent Systems: American Society of Mechanical Engineers (pp. 97-104).
Haberland, C., Elahinia, M., Walker, J. and Meier, H., 2013, September. Visions, concepts and strategies for smart Nitinol actuators and complex Nitinol structures produced by Additive Manufacturing. In ASME 2013 conference on smart materials, adaptive structures and intelligent systems (pp. V001T01A006-V001T01A006). American Society of Mechanical Engineers.
Haberland, C., Elahinia, M., Walker, J.M., Meier, H. and Frenzel, J., 2014. On the development of high quality NiTi shape memory and pseudoelastic parts by additive manufacturing. Smart Materials and Structures, 23(10), p.104002.
Habijan, T., Haberland, C., Meier, H., Frenzel, J., Wittsiepe, J., Wuwer, C., Greulich, C., Schildhauer, T.A. and Köller, M., 2013. The biocompatibility of dense and porous Nickel–Titanium produced by selective laser melting. Materials Science and Engineering: C, 33(1), pp.419-426.
Hagemann, R., Noelke, C., Rau, T., Kaierle, S., Overmeyer, L., Wesling, V. and Wolkers, W., 2015. Design, processing, and characterization of nickel titanium micro-actuators for medical implants. Journal of Laser Applications, 27(S2), p.S29203.
Halani, P.R. and Shin, Y.C., 2012. In situ synthesis and characterization of shape memory alloy nitinol by laser direct deposition. Metallurgical and Materials Transactions A, 43(2), pp.650-657.
Hamilton, R.F., Bimber, B.A., Andani, M.T. and Elahinia, M., 2017. Multi-scale shape memory effect recovery in NiTi alloys additive manufactured by selective laser melting and laser directed energy deposition. Journal of Materials Processing Technology, 250, pp.55-64.
HE, B.B., GU, D.D., WANG, L.F. and GUO, L.J., 2016. Numerical Simulation of the Thermal Behaviour of a Ti-Ni Shape Memory Alloy During Selective Laser Melting. Lasers in Engineering (Old City Publishing), 34.
Khoo, Z.X., Ong, C., Liu, Y., Chua, C.K., Leong, K.F. and Yang, S.F., 2016. Selective Laser Melting Of Nickel Titanium Shape Memory Alloy.
Krishna, B.V., Bose, S. and Bandyopadhyay, A., 2007. Laser processing of net-shape NiTi shape memory alloy. Metallurgical and Materials transactions A, 38(5), pp.1096-1103.
Krishna, B.V., Bose, S. and Bandyopadhyay, A., 2009. Fabrication of porous NiTi shape memory alloy structures using laser engineered net shaping. Journal of Biomedical Materials Research Part B: Applied Biomaterials, 89(2), pp.481-490.
Malukhin, K. and Ehmann, K., 2006. Material characterization of NiTi based memory alloys fabricated by the laser direct metal deposition process. Journal of Manufacturing Science and Engineering, 128(3), pp.691-696.
Malukhin, K. and Ehmann, K.F., 2007. Identification of direct metal deposition (dmd) process parameters for manufacturing thin wall structures from shape memory alloy (niti) powder. In 35th North American Manufacturing Research Conference, NAMRC 35.
Malukhin, K. and Ehmann, K., 2006. Manufacturing of shape memory alloy based monolithic functional structures with shape memory effect properties. In 34th North American Manufacturing Research Conference.
Malukhin, K. and Ehmann, K., 2006. Manufacturing of shape memory alloy based monolithic functional structures with shape memory effect properties. In 34th North American Manufacturing Research Conference.
Man, H.C., Zhang, S., Cheng, F.T. and Guo, X., 2005. Laser fabrication of porous surface layer on NiTi shape memory alloy. Materials Science and Engineering: A, 404(1), pp.173-178.
Mazzer, E.M., Kiminami, C.S., Gargarella, P., Cava, R.D., Basilio, L.A., Bolfarini, C., Botta, W.J., Eckert, J., Gustmann, T. and Pauly, S., 2014, July. Atomization and Selective Laser Melting of a Cu-Al-Ni-Mn Shape Memory Alloy. In Materials Science Forum (Vol. 802).
Meier, H., Haberland, C. and Frenzel, J., 2011. Structural and functional properties of NiTi shape memory alloys produced by selective laser melting. Innovative developments in design and manufacturing: advanced research in virtual and rapid prototyping, pp.291-296.
Meisel, N.A., Elliott, A.M. and Williams, C.B., 2015. A procedure for creating actuated joints via embedding shape memory alloys in PolyJet 3D printing. Journal of Intelligent Material Systems and Structures, 26(12), pp.1498-1512.
Meisner, L.L., Markov, A.B., Rotshtein, V.P., Ozur, G.E., Meisner, S.N., Yakovlev, E.V. and Gudimova, E.Y., 2015, October. Formation of microcraters and hierarchically-organized surface structures in TiNi shape memory alloy irradiated with a low-energy, high-current electron beam. In AIP Conference Proceedings (Vol. 1683, No. 1, p. 020145). AIP Publishing.
Meisner, L.L., Markov, A.B., Proskurovsky, D.I., Rotshtein, V.P., Ozur, G.E., Meisner, S.N., Yakovlev, E.V., Poletika, T.M., Girsova, S.L. and Semin, V.O., 2016. Effect of inclusions on cratering behavior in TiNi shape memory alloys irradiated with a low-energy, high-current electron beam. Surface and Coatings Technology, 302, pp.495-506.
Niendorf, T., Brenne, F., Krooß, P., Vollmer, M., Günther, J., Schwarze, D. and Biermann, H., 2016. Microstructural evolution and functional properties of Fe-Mn-Al-Ni shape memory alloy processed by Selective laser melting. Metallurgical and Materials Transactions A, 47(6), pp.2569-2573.
Oliveira, J.P., Panton, B., Zeng, Z., Omori, T., Zhou, Y., Miranda, R.M. and Fernandes, F.B., 2016. Laser welded superelastic Cu–Al–Mn shape memory alloy wires. Materials & Design, 90, pp.122-128.
Otubo, J., Rigo, O.D., Neto, C.M., Kaufman, M.J. and Mei, P.R., 2003, October. Scale up of NiTi shape memory alloy production by EBM. In Journal de Physique IV (Proceedings) (Vol. 112, pp. 873-876). EDP sciences.
Otubo, J., Rigo, O.D., Moura Neto, C.D., Kaufman, M.J. and Mei, P.R., 2004. Low carbon content NiTi shape memory alloy produced by electron beam melting. Materials Research, 7(2), pp.263-267.
Otubo, J., Rigo, O.D., Neto, C.M. and Mei, P.R., 2006. The effects of vacuum induction melting and electron beam melting techniques on the purity of NiTi shape memory alloys. Materials Science and Engineering: A, 438, pp.679-682.
Otubo, J. and Antunes, A.D.S., 2010. Characterization of 150mm in diameter NiTi SMA ingot produced by electron beam melting. In Materials Science Forum (Vol. 643, pp. 55-59). Trans Tech Publications.
Priyadarshini, B.G., Aich, S. and Chakraborty, M., 2011. An investigation on phase formations and microstructures of Ni-rich Ni-Ti shape memory alloy thin films. Metallurgical and Materials Transactions A, 42(11), pp.3284-3290.
Reyes Donoso, G., Reyes Donoso, G., Walczak, M., Walczak, M., Ramos Moore, E., Ramos Moore, E., Ramos-Grez, J.A. and Ramos-Grez, J.A., 2017. Towards direct metal laser fabrication of Cu-based shape memory alloys. Rapid Prototyping Journal, 23(2), pp.329-336.
Sadrnezhaad, S.K., Ahmadi, E. and Malekzadeh, M., 2009. Mechanism of reaction of molten NiTi with EBM graphite crucible. Materials Science and Technology, 25(6), pp.699-706.
Saedi, S., Turabi, A.S., Andani, M.T., Haberland, C., Elahinia, M. and Karaca, H., 2016. Thermomechanical characterization of Ni-rich NiTi fabricated by selective laser melting. Smart Materials and Structures, 25(3), p.035005.
Saedi, S., Turabi, A.S., Andani, M.T., Haberland, C., Karaca, H. and Elahinia, M., 2016. The influence of heat treatment on the thermomechanical response of Ni-rich NiTi alloys manufactured by selective laser melting. Journal of Alloys and Compounds, 677, pp.204-210.
Saedi, S., Turabi, A.S., Andani, M.T., Moghaddam, N.S., Elahinia, M. and Karaca, H.E., 2017. Texture, aging, and superelasticity of selective laser melting fabricated Ni-rich NiTi alloys. Materials Science and Engineering: A, 686, pp.1-10.
Shahverdi, M., Czaderski, C., Annen, P. and Motavalli, M., 2016. Strengthening of RC beams by iron-based shape memory alloy bars embedded in a shotcrete layer. Engineering Structures, 117, pp.263-273.
Shishkovsky, I., Yadroitsev, I. and Smurov, I., 2012. Direct selective laser melting of nitinol powder. Physics Procedia, 39, pp.447-454.
Shiva, S., Palani, I.A., Mishra, S.K., Paul, C.P. and Kukreja, L.M., 2015. Investigations on the influence of composition in the development of Ni–Ti shape memory alloy using laser based additive manufacturing. Optics & Laser Technology, 69, pp.44-51.
Silva, M.M., Pichon, L., Drouet, M. and Otubo, J., 2012. Roughness studies of NiTi shape memory alloy treated by nitrogen plasma based ion implantation at high temperatures. Surface and Coatings Technology, 211, pp.209-212.
Speirs, M., Van Hooreweder, B., Van Humbeeck, J. and Kruth, J.P., 2017. Fatigue behaviour of NiTi shape memory alloy scaffolds produced by SLM, a unit cell design comparison. Journal of the Mechanical Behavior of Biomedical Materials, 70, pp.53-59.
Straka, L., Soroka, A., Heczko, O., Hänninen, H. and Sozinov, A., 2014. Mechanically induced demagnetization and remanent magnetization rotation in Ni–Mn–Ga (–B) magnetic shape memory alloy. Scripta Materialia, 87, pp.25-28.
Walker, J., Andani, M.T., Haberland, C. and Elahinia, M., 2014, November. Additive manufacturing of nitinol shape memory alloys to overcome challenges in conventional nitinol fabrication. In ASME 2014 International Mechanical Engineering Congress and Exposition (pp. V02AT02A037-V02AT02A037). American Society of Mechanical Engineers.
Walker, J.M., Haberland, C., Taheri Andani, M., Karaca, H.E., Dean, D. and Elahinia, M., 2016. Process development and characterization of additively manufactured nickel–titanium shape memory parts. Journal of Intelligent Material Systems and Structures, 27(19), pp.2653-2660.
Yu, C., Kang, G., Kan, Q. and Zhu, Y., 2015. Rate-dependent cyclic deformation of super-elastic NiTi shape memory alloy: thermo-mechanical coupled and physical mechanism-based constitutive model. International Journal of Plasticity, 72, pp.60-90.
Zhang, B., Chen, J. and Coddet, C., 2013. Microstructure and transformation behavior of in-situ shape memory alloys by selective laser melting Ti–Ni mixed powder. Journal of Materials Science & Technology, 29(9), pp.863-867. Malukhin, K. and Ehmann, K., 2006. Manufacturing of shape memory alloy based monolithic functional structures with shape memory effect properties. In 34th North American Manufacturing Research Conference.
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