Effect of strain rate and temperature on the deformation behavior in a Ti-23.1Nb-2.0Zr-1.0O titanium alloy

The compression behavior of a Ti-23.1Nb-2.0Zr-1.0O (at.%) alloy was investigated at strain rates from 0.1 s(-1) to 1000 s(-1) and temperatures from 100 degrees C to 200 degrees C on a Gleeble 3800 system and Split Hopkinson Pressure Bar (SHPB) compressive tester. Optical microscopy, electron backscatter diffraction (EBSD), X-ray diffraction (XRD) and transmission electron microscopy (TEM) were employed to characterize the microstructure evolution during the deformation. Numerous deformation phenomena, including dislocation slip, twinning of both {332}< 113 > and {112}< 111 > modes, stress-induced alpha martensite (SIM alpha) and stress-induced omega (SI omega) transformations, were observed. The preferred activation of twinning and SI omega transformations was observed in the sample compressed at lower temperatures and/or higher strain rates. The underlying mechanism is that twinning and stress induced phase transformations are attribute to higher stress concentrations at beta grain boundaries and additional energy supplied by a higher strain rate, as well as high stacking fault energy because of higher temperature. (C) 2021 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.

Automated summary

The compression behavior of a Ti-23.1Nb-2.0Zr-1.0O alloy was investigated, revealing that twinning and stress induced phase transformations were preferentially activated at lower temperatures and/or higher strain rates.