Phase structure and site preference behavior of ternary alloying additions to PdTi and PtTi shape-memory alloys

Improvement in the Shape Memory Response of Ti50.5Ni24.5Pd25 High-Temperature Shape Memory Alloy with Scandium Microalloying

“…Therefore, a wide range of Sc solubility is expected in TiNiPd without second-phase formation. (2) According to currently unpublished atomistic simulations for quaternary additions to TiNiPd by Bozzolo, performed in a similar manner to the ternary additions studied by Bozzolo et al in TiNi [24] and TiPd and TiPt, [25] Sc was found to have a significant effect on the formation energy of TiNiPd, increasing the formation energy for a given unit of alloying addition more than any other element studied. Therefore, it can be inferred that Sc significantly affects the bond strength in the alloy, which may affect both the transformation and slip behavior.…”

The crystal chemistry of martensite in NiTiHf shape memory alloys

“…Bozzolo et al have reported the absolute site preference of elements in NiTi, PdTi, and PtTi systems based on atomistic modeling [28,29]. In NiTi the atomistic modeling predicts an energy gap of 6.21 and 4.26 eV for substitution of Hf in Ni and Ti sites, respectively [28].…”

Shape memory characteristics of Ti49.5Ni25Pd25Sc0.5 high-temperature shape memory alloy after severe plastic deformation

“…Improvements in the shape memory properties of a Ti 50.5 Ni 24.5 Pd 25 alloy after 0.5 at.% Sc addition have previously been shown [11]. Sc was initially chosen as an alloying addition based on the results of atomistic simulations of quaternary additions to TiNiPd, similar to previous work by Bozzolo et al for ternary additions to NiTi [31] and PdTi and PtTi [32]. Scandium was expected to have a wide range of solubility in TiNiPd, have a positive influence on the bond strength through an increase in the formation energy of the alloy, and increase the lattice strain, making it a potent solid solution strengthener.…”