RECRYSTALLIZATION BEHAVIOR IN Ti-13Cr-1Fe-3Al ALLOY AFTER SEVERE PLASTIC DEFORMATION

摘要

Ti-13Cr-lFe-3Al alloy was developed as an affordable priced titanium-based material for general use. Up to now, we've investigated mechanical properties, microstructures and heat treatment behaviors in the alloy. The grain size was refined to around 20 μm by thermo-mechanical treatments, dispersions of titanium boride or yttrium oxide, and so on. This means the grain size reaches the limit of conventional techniques in this alloy. Severe plastic deformation (SPD) has received considerable attention as a useful procedure for significant refinement of microstructures in metallic materials. In this study, recrystallization behavior was investigated in the Ti-13Cr-lFe-3Al alloy after high-pressure torsion (HPT), which is an SPD procedure. Vickers hardness rapidly increased with the number of turns (N) and saturated around 440 after N= 5. The HPT-processed specimen for N=10 was fully recrystallized at 1023 K for 5 min. Equiaxed crystals could be observed and the size reached about 6μm.