Adiabatic shearing behavior of shock-prestrained ti-2al-9.2mo-2fe alloy at different reloading strain rates

The effect of shock-prestrain on the adiabatic shearing behavior of a metastable β titanium alloy, Ti-2Al-9.2Mo-2Fe (2A2F), is systematically investigated. 2A2F alloy blocks with average grain size of 67 μm were first shock-prestrained at 6 and 12 GPa, and then reloaded at strain rates of 3000 and 4000 s-1. The results show that, the dynamic strength of 2A2F hardly increases after the shock prestrain. Adiabatic shear bands (ASBs) are more likely to bifurcate and interact, and the density of micro-damages and micro cracks in ASBs increases in the shock-prestrained materials. This trend becomes more significant with the increased preshock stress amplitude. However, in general, the amount of ASBs is low regardless of shock stress amplitude. The dynamic ductility is also hardly affected by shock-prestrain. These suggest that 2A2F alloy has good resistance to multiple impacts.