Microstructure and properties of multiphase V-Ti-Ni alloys for hydrogen separation alloy during asynchronous rolling

Abstract:

The asynchronous rollability of as-cast and heat treated multiphase V₆₀Ti₂₀Ni₂₀ alloys for hydrogen separation and the effects of different speed ratio on the microstructure, hardness and texture coefficient of the alloys were studied. The results show that the effect of asynchronous rolling process on improving the rollability of the alloys is higher than that of heat treatment process. Heat treatment plus asynchronous rolling can effectively improve the rollability of the alloys. The asynchronous rollability of the alloys increases with the increase of different speed ratio, and the hardness of the alloys hardly changes with the change of different speed ratio. The alloys show obvious rheological characteristics at high rolling reduction. V-based solid solution (Vss) and NiTi phase have large deformation and elongation along the rolling direction and form layered structure. With the increase of different speed ratio, the microstructure of the alloys gradually shows uneven deformation at a low degree along the thickness direction, and the deformation degree at the center is higher than that in synchronous rolling. The shear deformation introduced by asynchronous rolling along the thickness direction can weaken the rolling texture of the alloys to a certain extent.

Key words:multiphase V-Ti-Ni alloy; hydrogen separation; asynchronous rolling; microstructure; texture coefficient