SEVERE PLASTIC-DEFORMATION; SUPERPLASTIC DEFORMATION; TI-6AL-4V ALLOY; AL-MG; REFINEMENT; ECAP
MATERIALS RESEARCH SOCIETY
JOURNAL OF MATERIALS RESEARCH, v. 24, No. 6, Page. 2161-2165
A study was made to investigate cavity growth behavior during the superplastic deformation of submicrometer-grained titanium alloy and to compare that to cavity growth in a coarse-grained counterpart. A series of tension tests were performed at a temperature of 973 K and a strain rate of 10(-4) s(-1). Microstructures revealed that both the size and the volume fraction of the cavities obviously decreased as the grain size decreased. Working within the framework provided by creep models for understanding cavity growth behavior, we found the dominant growth mechanism to be superplastic diffusion, which leads to high-tensile ductility in submicrometer-grained titanium alloy.