Influence of Heat Treatment on Phase Transformation of Ni-rich TiNi Foils Produced <i>via</i> Ultrafine Laminates

Abstract

Using the ultrafine laminate method, thin foils (50 mm) of Ni-rich TiNi shape memory alloys were produced. Overall composition of the Ti/Ni laminate is Ti-50.7%Ni. TiNi (B2) phase was obtained after different diffusion treatments at 1073 K for 259.2 ks and 1173 K for 36 ks and 259.2 ks. Aging treatments at 773 K for 3.6, 18, 36, 72 and 144 ks were also performed. Multiple step martensitic transformation was observed for aged samples. The shape memory strain was 3:69 Â 10 À2 in the sample aged at 773 K for 18 ks.

Structure and mechanical properties of Ni/Ti multilayered composites produced by accumulative roll-bonding process

“…16 In this regard, Ti/Ni layered composite has received much attention due to its various applications, such as highly reflecting mirrors, monochromators, and polarizers in the neutron optics area. 17 This bi-metal multilayered composite is considered not only for its better physical or mechanical properties than those of monolithic Ni or Ti foils but also for its shape memory effects after annealing, [18][19][20][21][22][23] as well as its considerable heat generation after activation. [24][25][26][27][28] Ding et al 29 investigated the properties of NiTi shape memory alloy fabricated by the roll-bonding and subsequent annealing of the layered composite.…”

Bending Property of Super-Elastic Ti-Ni Alloy Dental Castings with Different Heat Treatments

“…Since the alloy possesses high corrosion resistance 1) as well as good biocompatibility, 2) it has been increasingly applied to medical and dental appliances, including vena cava filters, 3) self-expanding stents, 4) orthodontic wires 5) and coilsprings, 6) guidewires for catheters, endodontic rotary instruments, 7) and intermaxillary ligature wires. 8) With respect to the production of Ti-Ni alloys, research on sputter-deposited thin films, 9,10) melt-spinning technique 11,12) and ultrafine laminates 13) has been reported. Super-elasticity of Ti-Ni alloy is also expected to be useful for dental prostheses, especially for denture retainers such as clasps and bars.…”

Fatigue Property of Super-Elastic Ti&ndash;Ni Alloy Dental Castings

“…On the other hand, sputter-deposited thin films of Ti-Ni alloy showed superior shape memory effect, 9,10) and Ti-Ni thin sheets were fabricated by means of melt-spinning technique [11][12][13] and multilayers of Ti/Ni ultrafine laminates. 14) These thin sheets are expected to be useful especially for microactuators. [15][16][17] Since Ti-Ni alloy shows good corrosion resistance and biocompatibility 18,19) in addition to the special mechanical properties, it is the only practical metallic biomaterial with shape memory effect and super-elasticity.…”