Influence of the martensitic transformation on the hydrogenation properties of Ti50−xZrxNi50 alloys

Examination of Multiphase (Zr,Ti)(V,Cr,Mn,Ni)2 Ni-MH Electrode Alloys: Part II. Solid-State Transformation of the Interdendritic B2 Phase

“…[36,37] It was claimed that the martensite is favorable for the hydridation reaction; [20,38] the martensitic structure is able to store a much higher amount of hydrogen than the austenitic one, which could be relevant for electrochemical and storage applications. [36] Our conclusions on the presence of phases in the interdendritic grains differ from those offered in the articles by Song et al, [19,20] although the SAED patterns in both works appear to have very similar arrangement of spots. The alloys studied in References 19 and 20 are also of the AB 2 type, although they have different compositions: Zr 1-x Ti x (Mn 0.1 V 0.3 Ni 0.6 ) 2 (x = 0, 0.5) in Reference 19 and Zr 1Àx Ti x (MnVNi) 2.2 (x = 0, 0.2, 0.3, 0.4) in Reference 20.…”

Hydrogenation properties of shape memory Ti(Ni,Pd) compounds

“…To enlighten the effect of Pd substitution, it is very interesting to compare the present results with previous studies on Zr substitution [14,28,29]. Both substitutions allow the use of TiNi as SMA for high temperature applications.…”

“…Both substitutions allow the use of TiNi as SMA for high temperature applications. Previous works [29,30] report that, as a general trend, the martensitic transformation temperature rises linearly with the increase of Zr content in (Ti,Zr)Ni compounds. We here show that Pd substitution also increases martensitic transformation temperatures (Figs.…”

Microstructural analysis of the ageing of pseudo-binary (Ti,Zr)Ni intermetallic compounds as negative electrodes of Ni-MH batteries

“…Recently, Cuevas et al have demonstrated that this increase is related to the polymorphic properties of TiNi compound [12][13][14][15]. On cooling, the crystal structure of TiNi transforms at 325 K from the high-temperature cubic structure Pm3m (B2) into a monoclinic structure P2 1 /m (B19 ) [16,17].…”

“…−1 and 2.6 H f.u. −1 for austenitic and martensitic phases, respectively [13]. Hydrogen is absorbed in the austenitic phase as a solid solution, whereas hydrogen absorption in the martensitic phase occurs through the formation of two hydride phases of composition Ti 0.64 Zr 0.36 NiH and Ti 0.64 Zr 0.36 NiH 2.6 [14,15].…”