TiPd- and TiPt-Based High-Temperature Shape Memory Alloys: A Review on Recent Advances

Abstract

In this paper high-temperature shape memory alloys based on TiPd and TiPt are reviewed. The effect of the alloying elements in ternary TiPd and TiPt alloys on phase transformation and strain recovery is also discussed. Generally, the addition of alloying elements decreases the martensitic transformation temperature and improves the strength of the martensite and austenite phases. Additionally, it also decreases irrecoverable strain, but without perfect recovery due to plastic deformation. With the aim to improve the strength of high-temperature shape memory alloys, multi-component alloys, including medium- and high-entropy alloys, have been investigated and proposed as new structural materials. Notably, it was discovered that the martensitic transformation temperature could be controlled through a combination of the constituent elements and alloys with high austenite finish temperatures above 500 °C. The irrecoverable strain decreased in the multi-component alloys compared with the ternary alloys. The repeated thermal cyclic test was effective toward obtaining perfect strain recoveries in multi-component alloys, which could be good candidates for high-temperature shape memory alloys.

Laser-assisted synthesis of metallic composite nanostructures in aqueous solutions

“…Synthesis of bimetallic nanocomposites between Au, Pt, Pd or Zn in water colloids with Ti, observed in the experiments and described above, could be explained by a complex dependence between the thermodynamic properties and effects, electron structure, miscibility, concentration etc. of each of the components [13,14] of the colloid. Moreover, the water environment and the water column height, as well the laser beam parameters like wavelength, pulse duration, energy per pulse, and repetition rate could crucially influenced on the thermodynamic process occurred during laser irradiation of the colloid.…”

Novel Candidates for Palladium Alloys – Enhanced Strength and Ductility - Generalized Stacking Fault Energy Calculations

“…For this reason, we cannot compare our results with any other alloys. On the other hand, Ti-Pd alloys are widely studied due to their high martensitic transformation temperature (MTT) [28]. The increase of the Ti concentration in Pd reduces the MTT which may be due to the facilitation of crystal plane slip.…”

Shape Memory Alloys 2020

“…Raising the martensitic transformation temperature of SMAs (above 100 • C) is still a challenge, although there are already some materials that are used in different applications. In this Special Issue, Yamabe-Mitarai reviewed TiPd and TiPt-based alloys as important families of high-temperature SMAs [1]. In the context of a detailed investigation it was concluded that multi-component alloys can be good candidates for HT-SMAs, indicating as well that the limitations that need to be overcome entail the suppression of the transformation strain reduction and temperature hysteresis increment.…”