Grain size effect on the R-phase transformation of nanocrystalline NiTi shape memory alloys
نویسندگان
چکیده
This study investigated the effect of nanograins size on the R-phase transformation of a nanocrystalline Ti-50.2at%Ni alloy. The nanometric grain size was created by severe cold deformation and low temperature anneal. It was found that in the recrystallized state, nanograin sizes (<100 nm) was effective in suppressing the B2→B19’ martensitic transformation and revealing the B2↔R transformation. The B2↔R transformation temperature was found to increase with decreasing grain size within the range of 22-155 nm.
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