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Massive technological developments can produce material functionality with a wide variety to meet various needs such as flexibility and smart devices, one of which is shape memory alloy (SMA) material. SMA is a smart material that is unique in remembering its original shape even though it has undergone load deformation above the elastic limit due to temperature or load stimulation. Ni-Ti-based is one of the well-established SMA materials, compared to Cu-based and Fe based. Shape memory alloy made from iron, also known as shape memory steel, is widely used in various applications due to various advantages over NiTi. In its development, Iron-Based SMA was applied to various fields, including civil engineering, mechanical engineering, and biomedical. The use of Fe as an alternative material in the application of shape memory alloys has advantages such as low processing costs and the availability of abundant raw materials. Fe-based SMA properties such as ductility, magneticity, strength, biocompatibility, and bioactivity are used in various biomedical applications, including cardiovascular stents and bone prostheses. Other advantages found in Fe-based SMA are weld-ability, ductility, elastoplastic damping and strain hardening due to deformation induction ɣ to ɛ martensitic transformation. However, there is still lack of research that discusses the use of Fe-based SMA in biomedical applications. Some of the reasons are instability, impracticability and poor thermo-mechanic performance, which results in a low percentage of shape recovery. This is an opportunity to encourage research and development in optimizing Fe as an alternative shape memory material. This review will provide an overview of the development of Fe-based SMA materials, especially in the biomedical field. In addition, discussions related to challenges and opportunities will also be described based on the research results that have been carried out to date. [ABSTRACT FROM AUTHOR]

Due to their biocompatibility, superelasticity, and corrosion resistance, binary and ternary NiTi (NiTiNOL) shape memory alloys (SMAs) are at the forefront of materials research for biomedical applications. The first half of the study reviews the biocompatibility and uses of NiTi SMAs. Traditional machining techniques have difficulty dealing with binary and ternary NiTi SMAs. The second half of the research discusses the literature review of unconventional SMA machining techniques from laser beam to wire electrical discharge machining (Wire EDM). Significant output responses, such as surface roughness and material removal rate, are also investigated as a function of numerous non-traditional machining process input factors. The conclusion outlines the few areas of research that remain to be done on the subject of NiTiNOL SMAs' machinability. [ABSTRACT FROM AUTHOR]

Porous Nickel-Titanium (NiTi) alloy has been developed especially in the biomedical sector due to its shape memory ability and its mechanical properties which is comparable to human bones. However, NiTi alloy carries the risk of Nickel (Ni) ions leaching when implanted in the human body making it less favourable for biomedical use forlong term. Therefore, the goal of this research is to passivate the porous NiTi by oxidizing the surface via annealing treatment. Initially, the porous NiTi alloy was fabricated via powder metallurgy technique with addition of Calcium Hydride (CaH2) as a pore forming agent. Here, the degree of porosity was measured and the pore morphology, phase identification and transformation behavior were characterized by Scanning Electron Microscope (SEM), X-Ray Diffractometer (XRD), and Differential Scanning Calorimeter (DSC), respectively. Then, the surface treatment was performed by varying annealing temperatures where the oxide layer formation was characterized by using SEM and Energy Dispersive Spectrometer (EDS). The result shows that the sample's porosity increased by up to 42% from its theoretical density, demonstrating that the weight percentage of the pore-forming agent has a significant effect on theporosity of the NiTi alloy. For surface treatment, at higher annealing temperature i.e. 500°C, it produced a thicker oxide layer of TiO2 as compared to samples annealed at 300°C and 400°C. This indicates that the annealing temperature highly affects the formation of oxide layers on the surface. This oxide layer adheres well to the NiTi alloysurface and is expected to prevent the Ni ion from releasing, thus making this porous NiTi biocompatible metal. [ABSTRACT FROM AUTHOR]

This study emphasizes on Shape memory alloys (SMA) essentially NiTinol, which is extensively used in development of composites in the form of a reinforcement either as a fiber or particulate which help in improving the mechanical properties, providing it the dynamism due to the presence of uniqueness in the property of shape memory upon change in temperature. SMA is super elastic and have the ability to recover. NiTinol is used as an alternative to many traditional smart structures used in bulk, it is also used to embed in the development of an actuator, morphing of blades with embedded strips, in carbon fiber reinforced polymer composites, MMC's and many more applications to improve the properties of the composite. The study focuses on the SMA, NiTinol in specific, its properties, fabrication techniques and its phases. Due to excellent mechanical properties, there are numerous applications in various sectors and domains where they are actively being used in Structural Design, in medical fields and also in Space research domain as well. Hence this comprehensive study gives an innate understanding of shape memory alloys and its properties, their phases and fabrication techniques with their applications which imbibes various unique properties to the composites. [ABSTRACT FROM AUTHOR]

This manuscript covenant by means of the random natural rate of recurrence analysis of hybrid composite plate by employing the finite element (FE) based numerical approach. Shape memory alloy (Nitinol) in the form of rods will be inserted in glass epoxy composite plates to obtain the hybrid composites. An algorithm is resultant for vagueness quantification of accepted frequencies of the hybrid composite owing to uncertain disparity in the substance properties. This deterministic finite element code is verified with the preceding copy. The effects of degree of randomness and specific volume on the first three natural frequencies will be determined. Monte Carlo simulation will be coupled with finite element code to conduct the random analysis. The outcome demonstrates the key in parameters painstaking in the current learning have momentous possessions on the randomness of initial three accepted frequencies of plank hybrid composite plates. [ABSTRACT FROM AUTHOR]

Smart material alloys are researched and used in various applications due to their superelastic, mechanical properties, and shape memory effects. The smart material used in this project is a Nickel-Titanium (Nitinol) alloy. In this study, research is conducted to use Nitinol as a pair of coiled muscles for the flexion and extension - actuation processes and also to check their biocompatibility. The unique arrangement of nitinol springs actuators enables the robotic hand to curl and uncurl its fingers, to hold something. It has a design power requirement of a minimum of 14 watts. The shape setting of nitinol wire of 0.4mm dia to form springs was carried out by firmly constraining it on a mandrel and then performing heat treatment. A series arrangement of nitinol springs along the forearm is implemented into a hand model after deliberation of different designs. Its activation is done using a joule heating approach. Finally, the performance characteristics of these nitinol spring actuators would be compared with the traditional robotic actuators and conclude this study. [ABSTRACT FROM AUTHOR]

This work aims to evaluate the force-deflection behavior of NiTi shape memory alloy archwire towards the effect of friction in orthodontic leveling. A universal bending jig setup was developed to perform three-point bending, two-bracket bending, and three-bracket bending tests at room temperature (27°C). The three-point bending setup follows the ISO 15841 standard and is then modified to compensate for the setup of bracket bending tests. Two different wire sizes were used; 0.014-in and 0.016-in NiTi round archwire, and 0.016-in × 0.022-in and 0.018-in × 0.025-in NiTi rectangular archwire, coupled with 0.022-in stainless steel brackets. The polytetrafluoroethylene (PTFE) bracket is resembling a frictionless bracket used as a control experiment. The force-deflection behavior of the NiTi archwire mounted on the PTFE bracket/support showed a flat plateau of force at stress-induced martensitic phase transformation (SIMT) at activation and deactivation stages, in all bending configurations. However, the use of the stainless-steel bracket/support causes a positive and negative gradient in the activation and deactivation of the force. The force gradient is, even more, steeper in the three-bracket configuration compared to the two-bracket configuration. On the other hand, the sliding friction is determined at the bending point while the binding friction is determined at the bending point. The frictions that have occurred vary depending on the size and shape of the wire. The presence of friction increased the force required to deflect the orthodontic wire to the prescribed deflection distance. The negative gradient of the force plateau during wire deactivation may prevent the deflected wire from being fully recovered. [ABSTRACT FROM AUTHOR]

This work is focused on a TPMS primitive unit cell, modeled with NiTi as a base material and subjected to cyclic loading. Its functional fatigue behavior is analyzed via an FEM model, and the appropriate post-processing of the data. Full periodic boundary conditions are applied onto each of the cell's faces, to simulate an infinitely-large structure. The loading and unloading surfaces, from the first unloading onwards, depend on the accumulation of the martensite phase, due to a residual stress field. This effect, functional fatigue, is taken into account to derive loading and unloading surfaces via double interpolation. This double interpolation is done from the information of calibration cases. Then, it is validated with a different loading path. This facilitates the prediction of the functional cyclic behavior of primitive TPMS cells made of NiTi. [ABSTRACT FROM AUTHOR]

The regime of heat treatment (annealing at 1448 K, 8 h with quenching in water), which leads to the appearance of thermal-induced martensitic transformation in [001]-oriented Ni42Fe19Ga27Co12 (at.%) single crystals was experimentally established. The large regions of γ-phase in size of 50−500 µm and volume fraction of∼20–25% were precipitated during annealing. The γ-phase leads to a decrease in the content of iron and cobalt and an increase in the content of gallium in the matrix; reduction of stresses for oriented martensite formation in stress-assisted thermal cycles by 4 times (from 200 to 50 MPa); broadening of thermal hysteresis in stress-assisted thermal cycles and stress hysteresis in loading/unloading cycles; a shift of superelasticity temperature range to higher temperatures. [ABSTRACT FROM AUTHOR]

This investigation comprises a study of the influence of the silicon on the morphology, topographical parameters, and deformation behavior of the Ti-N-Nb and Ti-Ni-Nb-Si surface alloys (SAs) formed on the NiTi-substrate by the electron-beam synthesis. It was shown that addition of Si10 (at. %) to the chemical composition of sputtered film during electron-beam synthesis of SAs leads to smoothing of the surface microrelief with the average roughness parameter R a I N T ≈ 0.211 μm , that ∼1.7 times lower than compared to its value in SA without silicon ( R a I N T ≈ 0.355 μm). The presence of silicon in SA leads to a high value of the yield strength (σy≈3.3 GPa), values of which monotonically decrease from the surface to the values of NiTi-initial. Evaluation of the deformation behavior showed, that in surface layers of synthesized SAs, due to an increase of plasticity, there was a decrease in superelasticity by no more than ∼5%. This result shows that the presence of SAs on the surface of NiTi-substrate will not lead to a significant decrease of the superelastic properties of NiTi-substrate. [ABSTRACT FROM AUTHOR]

The responses of two models of heterogeneous medium to impact loading are compared, namely, the direct numerical simulation model and the additive mixture model. Verification of Ni and Ti material parameters in the simulation of spall in a homogeneous barrier is performed. The calculated free surface velocity for homogeneous plates corresponds to the experimental data with an accuracy of at least 10%. A simulation of the impact loading process of plates made of Nitinol based on mathematical models of heterogeneous materials has been performed. The additive mixture model more accurately reproduces the free surface velocity profiles than direct numerical simulations. Nevertheless, the deviation of numerical simulation results from experimental data does not exceed 10% for both models. A comparison of the results of the models' responses to impact loading has shown that it is acceptable to use both models in problems considering alloys as heterogeneous media. [ABSTRACT FROM AUTHOR]

The study of the structure of the melted metal at the boundary of the explosion-welded composite titanium VT1-0 - Cr20Ni80 nichrome was carried out. It has been established that areas of chemical microheterogeneity are formed at the interlayer boundary in the form of local inclusions of melted metal of the NiTi(Cr) composition and continuous interlayers based on nonequilibrium solid solutions (Ti, Ni, Cr). The calculated cooling rates of the melted metal showed the possibility of the formation of non-equilibrium phases and amorphous structures characterized by the absence of a long-range order in the arrangement of atoms. [ABSTRACT FROM AUTHOR]

Recently, near-equiatomic TiNi alloy has been recognized as a successful alternative to replace traditional of next generation Ti alloy for biomaterial applications. This is owing to its distinctive shape memory effect in addition to lower young modulus. Ti alloy is known for many years as crucial alloy in aerospace applications, which is utilized for the airframe and the engine parts. This is rationalized to reduce fuel consumption due to lower density for the alloy. However, aerospace materials still suffer from inadequate fretting wear, corrosion and stress corrosion cracking. It has been reported that the tribology behavior of NiTi alloy is better than many conventional alloys. Consequently, this study has been emerged to evaluate the progress in developing NiTi alloy. [ABSTRACT FROM AUTHOR]

Clothing for protection against critical low temperatures is constantly being improved. Modern materials and alloys with shape memory are used for its production. This article presents a method of incorporation of such materials into textile structures. The peculiarity of these alloys is shape memory as a result of training in a different temperature range taking into account the influence of various impurities. The purpose of this article is to develop and evaluate a methodology for shape memory training of functional parts for use in clothing at negative temperatures. In the course of the research, the current conditions for training materials with shape memory that differ in the boundary temperatures, the number of training cycles and the ways of forming the thermal conditions were investigated, The object of this article is thin metal- coated threads (wires) based on the binary alloy of nickel and titanium - Nitinol (NiTi). The geometric parameters of the thread (thin wire) are justified by the geometric parameters of the textile structure, which is specially designed to determine the diameter of threads set at 0.5 mm (based on the mean thickness of materials for winter protective clothing). A thermomechanical training technique was developed. It takes into account the chemical composition of the NiTi-based functional alloy, loading mode, rest mode, number of training cycles, fixation of the desired shape (using a steel mandrel) for set temperature conditions (that are assured by an autonomous refrigerated container and thermostat). Two phase shapes of a thin part were studied - a straight shape and an angular bend shape (for an angle of 2 degrees). It has been established that the developed method of thermomechanical training, including 200 cycles of training and temperature interval from +200C to -180C allowed achieving the form memory effect for trained parts with its direct and reverse response to the change of set temperatures. The obtained result makes it possible to embed the prepared thin metal threads (wires) into the textile structure to control the shape of the volume and overall thermal insulation of the functional clothing for protection against the cold. [ABSTRACT FROM AUTHOR]

Fibers are utilized in a variety of ways to reinforce cement products (such as concrete). The behavior of shape memory alloys SMA nanofiber reinforced cement effect is the subject of this research. The shape memory alloy used in this investigation is NiTi. Cement is slump tested, is put to the test for seven days. SMA nanofibers are added to the cement mix at a constant rate of 4% wt. SAM micro powder and SAM microfiber reinforced cement are also made,mechanical parameters such as compressive strength and and bending strength are examined for 7 days. Results are compared to SMA nanofiber reinforced cement. cement reinforced with 4% nitinal PVA nanofibers improved Compressive strength to 47 MPa comparer with 18, MPa for standard cement-sand, while decrees deflection to 0.048mm compare with 0.11,0.249 and 0.26 for standard cement-sand, nitinol to cement and microfiber /standered cement sample respectively. [ABSTRACT FROM AUTHOR]

Shape memory alloys exhibit interesting phenomena termed as shape memory effect, which occurs at a specific composition for a class of materials when alloyed together. In current work, we consider Nickel and Titanium (nitinol) which exhibits this interesting phenomena at near equiatomic composition. In a quest to develop a structure-property correlation, it is expected that among other parameters, defects in the materials also contribute towards the properties of material developed. As a result, stacking fault energy is one such defect which decides the properties of materials. The current work estimates the staking fault energy of nitinol based alloy system from second nearest neighbor embedded atomic model using molecular dynamics simulation that allows to establish a structure-property correlation. [ABSTRACT FROM AUTHOR]

The paper presents the results of studying the effect of thermal cycling modes of TN-1 alloys on thermocyclic creep and related irreversible deformation. It is shown that non-isothermal creep of these materials is maximal at thermocycling through martensitic transitions interval during free state cooling and heating under load. [ABSTRACT FROM AUTHOR]

The paper presents the analysis of the research data on the investigation of the local deformation behavior and mechanical properties of the surface layers of NiTi alloy depend on the shape of the indenter's tip (Vickers and Berkovich). Investigations of the mechanical properties (microhardness HOP, Young's modulus EOP, parameter of plasticity δh, and shape recovery ratio η) of the surface layers of NiTi alloy were held by the method of instrumented indentation test. The analysis of the experimental data shows, that at a maximum load Pmax from ∼5 up to ∼300 mN, the deformation behavior of the surface layers of the initial NiTi samples under instrumented sharp indentation with tips of different shapes are similar at a surface layer of ∼1 µm thickness. It means that, regardless of the shape of the indenter's tip, almost identical stress and strain states are created in the indentation zone and adjacent areas. [ABSTRACT FROM AUTHOR]

Nitinol shape memory alloy (SMA) exhibits distinctive characteristics like biocompatibility, shape memory effect, Pseudoelasticity, high resistance to oxidation, superior functional stability. Owing to these superior properties, Nitinol SMA becomes favourable choice for automotive, actuators, biomedical applications, aerospace industries and micro-electromechanical systems (MEMSs). The traditional machining techniques for Nitinol SMA imposes multiple difficulties owing to its characteristics like high toughness, lower strain hardening effect, increased ductility, and improved chemical reactivity. Wire-Electric Discharge Machining (WEDM) through powder-mixed dielectric is one such technique which is mostly suitable for difficult-to-cut materials. In current study, pulse-on-time (Ton), pulse-off-time (Toff), current, nano-graphene powder concentration were designated as machining parameters while SR as response variable for the WEDM of nitinol SMA. Design of experiments (DOE) was employed to create the experimental matrix with total of 27 experiments to be performed. Analysis of variance (ANOVA) was employed to study the statistical analysis of the obtained results. Influence of machining variables on SR response has been investigated by using main effect plots. 3D surface plots were incorporated to understand the simultaneous effect of two variables on SR. Best parameter combinations for obtaining the lowest SR value was determined from the analysis. Authors believes that present work will be useful in the area of powder-mixed machining of Nitinol SMA. [ABSTRACT FROM AUTHOR]

In this paper we establish, on the basis of calorimetric measurements by direct reaction, new values of enthalpies of formation of the ternary intermetallic compounds (Ni3Ti(Al), NiTi(Al) and NiTi2(Al)) of ternary phases based on the system Ni–Ti at 1073 K. Precisely, we determine the variation of the enthalpies of formation of ternary compounds with the substitution of Aluminium atoms by Titanium at Nickel constant concentration. Then structures, compositions and limits of solubility of these ternary phases were investigated by X-ray powder diffraction (XRD) and electron probe microanalysis (EPMA). This last technique was also used to determine the limits between Ni3Ti(Al), NiTi(Al) and NiTi2(Al) solid phases in the isothermal section of the Al-Ni-Ti diagram at 1073 K. Our experimental results are compared with literature data and with predicted values based on semi–empirical and theoretical models. [ABSTRACT FROM AUTHOR]

Nowadays with an abundance of wire alloys to choose for orthodontic treatment, dentists must be wise to select an appropriate wire for the treatment while considering its biological effects on the patient. This review will discuss the possible genotoxic effects of NiTi alloy (Nitinol) orthodontic wires caused by metal ion release. Essentially, the release of metal ions promotes ROS production and induces oxidative stress, which will potentially oxidize nucleotide bases and could cause mutations. Even though the release of metal ions cannot be fully avoided, attempts could be made to minimize its effects on the human body. Clinicians should be aware of the patient's relevant status (such as hypersensitivity) and get updated on newer wire alternatives to optimize the patient's treatment while avoiding undesirable biological effects. [ABSTRACT FROM AUTHOR]

In this work, the thermomechanical stability of heterophase [001]-oriented Ti–51.5 at % Ni single crystals was investigated. Experiments include a high-temperature and high-stress martensite ageing and also loading/unloading cycling at superelasticity (SE) during forward and reverse B2-B19′ martensitic transformations (MT). It was found that Ti–51.5 at % Ni single crystals containing large Ti3Ni4 particles (d ∼ 600 nm after ageing at 850 K for 1 h) is not resistant to stress-assisted martensite ageing and cycling. Stress-assisted martensite ageing at 423 K, 1.7–2 GPa, for 2–4 h leads to the deformation of large Ti3Ni4 particles, the appearance of dislocations at the particle-matrix boundaries, an increase in MT temperatures (by 10 K), and a strong diffusion of the MT (the intervals of forward and reverse MT Δ 1 σ and Δ 2 σ increase in 2 times). During loading/unloading cycling at 423 K and 1.0–2.0 GPa single crystals with large particles were destroyed after 20–25 cycles. It is possible to increase the thermomechanical stability due to the additional precipitation of nanosized Ti3Ni4 particles (d<30 nm by ageing at 673 K, 1 h), which appear in the B2 matrix between large particles. In such crystals with a bimodal structure no changes in the microstructure and functional properties were observed after stress-assisted martensite ageing and loading/unloading cycling. [ABSTRACT FROM AUTHOR]

A study was carried out of the effect of crystal structure on the two-way shape memory effect (TWSME) and its cyclic stability using ferromagnetic single crystals of the Co49Ni21Ga30 alloy (at %), oriented along the [001]-direction, after quenching (T = 1423 K, 0.5 h) and stress-free ageing (T = 623 K for 3 h). The TWSME in [001]-oriented single crystals of the Co49Ni21Ga30 alloy was manifested after training of samples during implementation of B2-L10 martensitic transformation (MT) in the cooling/heating cycle, with constant external stress |σext|. The value of the TWSME was found to depend on the structure of the crystals and the level of applied stress during training. The maximum TWSME value (εTWSME = –4.3(±0.2)%) was achieved after training at |σext| = 125 MPa in single-phase crystals and was equal to lattice deformation ε0 in MT for [001]-oriented single crystals under compression. Ageing lead to a decrease in the TWSME value compared with the single-phase state in three times. In [001]-oriented single crystals with γ′-phase particles, the value of TWSME εTWSME, the temperature hysteresis ΔTTWSME, and the start temperature of the forward MT Ms remained unchanged for 500 cycles, and in quenched crystals, up to 150 cycles. [ABSTRACT FROM AUTHOR]

The development and implementation of organ-preserving treatment methods in patients of reproductive age is the priority trend in modern oncology. The results of using high-tech methods developed at Tomsk Cancer Research Institute were discussed. The technique of forming the obturator apparatus of the uterus using the superelastic nitinol mesh implant was presented, and high efficacy of this implant in terms of pregnancy outcome was shown. The reproductive results and recommended methods of assisted reproductive technologies for this category of patients were analyzed. In conclusion, recommendations for the application of high-tech methods for radical trachelectomy, as well as guidelines for follow-up care and delivery in patients with cervical cancer after radical trachelectomy were given. [ABSTRACT FROM AUTHOR]

The present investigation aims at studying the mechanical properties like microstructure, grain refinement shape memory effect and martensite transformation behavior of Cu-Al-Ni Shape Memory Alloys and it has been studied thorough EDAX, Optical Microscopy (OM) and Differential scanning Calorimetry (DSC). From the investigation it is found that shape memory effect of the Cu-Al-Ni alloys is able to display at a specific composition of about 12-14 wt.%for aluminum and 3-5 wt.% for nickel. Bend test is used to study the properties of shape memory alloys.Various mechanical tests were carried out on the specimen which shows maximum shape memory effect. It is observed that the composition of Cu(81.8) Al(13.7) Ni(4.5) shows the best shape memory effect and it is calculated to be 95.66 (%). It is found that alloys show better hardness property as well. [ABSTRACT FROM AUTHOR]

Shape Memory Alloys (SMAs) are a peculiar class of materials able to recover their initial shape by a phase solid transformation thermally activated. The research activity is focused on the characterization of corrosion behavior of Cu-Zn-Al SMA. Potentio-dynamic anodic polarization tests and electronic microscopy (SEM-EDS) observations of corroded surfaces have been carried out in order to analyze corrosion resistance to different chemical environments. [ABSTRACT FROM AUTHOR]

This paper reports investigation results of microstructure transformation and shape memory property in Cu- 22Zn-7Al (wt%) shape memory alloy in the heat treatment process with the variable of various quench mediums. The alloy was made by the melting process of Cu ingot, yellow brass, and Al ingot. Molten metal was poured and solidified in a permanent mold. Then, solid Cu-22Zn- 7Al alloy was heat treated by homogenizing and stress relief annealing. Martensite of the alloy was formed by heating Cu-22Zn- 7Al in Beta phase temperature then continued by cooling in air, oil, water, and brine. Each cooling medium has a different effect on cooling rate. Chemical composition, microstructure, non- equilibrium transformation temperature, hardness, and shape memory properties were investigated in detail. The result shows that the martensite phase increases by enhancement of cooling rate. Alloy quenched by brine not only performs the best quality of martensite but also exhibits the highest shape memory recovery. [ABSTRACT FROM AUTHOR]

Cu-Al-Mn ternary shape memory alloys (SMAs) obtained through ingot metallurgy process by using induction furnace. Specimens prepared by varying percentage of aluminium (10-15wt. %) and manganese (2-10wt.%). Application of these SMAs requires it to be fabricated to required shape. Machinability of SMAs has not been investigated to shape the alloy. In the present work machining characteristics of Cu-Al-Mn ternary shape memory alloys are investigated by WEDM machining process. The effect of input parameters like Current (I), Diameter of the wire (D) and Wire Speed (S) on Material Removal Rate (MRR) in WEDM of Cu-Al-Mn ternary shape memory alloys was studied. The WEDM specimens and cross section of ternary alloys were analyzed using Scanning Electron Microscope. The obtained results indicated that, the MRR increases with increase in wire speed and diameter of the wire. A SEM image indicates the surface morphology of the machined surface. [ABSTRACT FROM AUTHOR]

Modifications achieved by laser irradiation on titanium-base alloys were studied to promote their surface properties in addition to the ion release behavior. Laser pulses was use for three different types of Ti-base alloys; commercial pure Ti alloy, Titanium-Tantalum alloys, and Nickel-Titanium alloys. The alloys were manufactured by using powder technology then the Nd: YAG laser pulses were used. The characterizations of samples have been done which includes; microstructure observation, XRD, surface roughness (AFM), and ion release analysis. The microstructure observation show that the use of Nd: YAG laser pulses was effective method to provide energy focused on one spot especially at the surface which produce complex microstructures and roughening the surfaces to increase effective surface area. XRD showed the sintering process under controlled atmosphere produced samples with complete sintering reaction. AFM results show the same response to the laser irradiation and the slight differences in the roughness values was observed. From the results of ion release analysis it was found that the release of Ti ion rise in first three days and after that released of Ti ions begin to stabilize after the laser pulses. The appearance of a slight differences in the amount of titanium ions that released from the samples for each group was due to the influence of the surface activation process that have been employed as a primary treatment which effect on the stability and thickness of the titanium oxide. [ABSTRACT FROM AUTHOR]