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Uniaxial compression tests were performed on Ti–47Al–2Cr–2Nb alloy at a temperature range of 288 K–773 K. The mechanical response and microstructure of Ti–47Al–2Cr–2Nb alloy after uniaxial compression were systematically analyzed. Investigation on mechanical properties show that under dynamic compression, the yield strength and ductility of Ti–47Al–2Cr–2Nb alloy remain almost same at all loading temperatures, while the strain hardening rate of the Ti–47Al–2Cr–2Nb alloy present an obvious declining trend with the increased loading temperatures, resulting in the decreasing of ultimate compressive strength. Failure analysis reveals that under quasi-static compression, the failure mechanism of Ti–47Al–2Cr–2Nb alloy is micro-porous coalescence failure in α2 phases. Under dynamic compression at a temperature range of 288–773 K, shear failure is the main failure mode of Ti–47Al–2Cr–2Nb alloy. It is interesting to find that at a temperature range of 288 K–373 K, the failure mechanism of Ti–47Al–2Cr–2Nb alloy is brittle shear failure owing to the rapid propagation of micro-cracks along the lamella interface. When the loading temperature increases over 473 K, adiabatic shear band (ASB) is observed, indicating that the failure mechanism of Ti–47Al–2Cr–2Nb alloy transfers from brittle shear failure to adiabatic shear failure. |
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