Concept of mechanocaloric granular material made from shape memory alloy

Superelasticity degradation of NiTi shape memory alloy in wide ranges of temperature and loading level: Experimental observation and micromechanical constitutive model

Development of a constitutive model considering functional fatigue and pre-stretch in shape memory alloy wires

Multiscale plasticity behavior and fatigue performance of laser melting multi-layer nickel-based superalloys upon heat treatments

The significance of advanced smart materials in recent technological research and advancement is apparent from its extensive use in present day devices and instruments. Of the various smart materials in use today, the fascinating category of shape memory alloys (SMAs) is equipped with the ability to return to a previously memorized shape under certain thermomechanical or magnetic stimuli. The unique property of shape memory effect and superelasticity displayed by these materials along with good biocompatibility and corrosion resistance make them ideal for biomedical applications. The various applications of SMAs in surgical instruments, surgical implants, and assistive and rehabilitative devices have significant effect on the day to day life of people in the present age. Majority of these biomedical devices belong to the orthodontic, orthopedic, or surgical fields. Other remarkable applications of SMAs such as in the production of prostheses and orthoses designed through the biomimetic approach are also highly influential in improving the quality of life. The present paper provides an overview of the various properties of shape memory alloys and their applications in the biomedical field over the years, that have had a significant impact on the realm of medical science.

The role of NiTi shape memory alloys in quality of life improvement through medical advancements: A comprehensive review

A multi-physics, multi-scale and finite strain crystal plasticity-based model for pseudoelastic NiTi shape memory alloy

Evolution of transformation characteristics of shape memory alloys during cyclic loading: transformation temperature hysteresis and residual martensite

Concentration of transformation-induced plasticity in pseudoelastic NiTi shape memory alloys: Insight from austenite-martensite interface instability

The coupling between transformation-induced plasticity (TRIP) and low cycle fatigue of pseudoelastic shape memory alloys (SMAs) is investigated and an upper bound of low cycle fatigue life is found. Through combined in-situ infrared and digital image correlation observations on NiTi sheets, we reveal that the low cycle fatigue of SMAs is governed by the transformation band fronts with the highest temperature where TRIP is maximized. The local state at the band front is in fact determined by a coupling effect of the applied loads and thermal conditions, the former driving the transformation with heat release while the latter determining the heat transfer efficiency. This coupling leads the fatigue lives to distribute along a series of isotherms. As the coupling tends to be infinitesimal, local TRIP is limited to a minimum level, thus resulting in an upper bound of low cycle fatigue life. This agrees well with the experiments.

Xiaofei Ju

Papers

A multi-physics, multi-scale and finite strain crystal plasticity-based model for pseudoelastic NiTi shape memory alloy

Evolution of transformation characteristics of shape memory alloys during cyclic loading: transformation temperature hysteresis and residual martensite

Concentration of transformation-induced plasticity in pseudoelastic NiTi shape memory alloys: Insight from austenite-martensite interface instability

The upper bound of low cycle fatigue life of pseudoelastic polycrystalline NiTi shape memory alloys