Adiabatic shear sensitivity performance of Ti-1023 alloys at different heat treatment regimes
Using the Hopkinson pressure bar test system to conduct room temperature dynamic com-pression experiments for cylindrical samples,the formation characteristics of adiabatic shear bands and the microstructure of Ti-1023 titanium alloy under different heat treatment regimes were studied.The results show that the grain size of Ti-1023 alloy is increased by the solid solution treatment above the phase transition point.The fine acicular α phase precipitates at the β grain boundary.The solid solution aging below the phase transition point causes a large number of spherical α phases in the grains,and the grain size of the tissue grains with dual aging treatment is even smaller.Under the loading conditions of different strain rates,all different tissues show obvious strain rate enhancement and plasticizing effect,reflecting apparent characteristics of thermoplastic instability.The dynamic strength of the solid solu-tion aging group above the phase transition point was the highest,but the plastic difference was the worst and being presented with the greatest adiabatic shear sensitivity.It is the most difficult to produce adiabatic shear in the solid solution single aging structures below the phase transition point,but the ma-terial strength is low.The solid solution dual aging tissue has higher dynamic strength and better plasti-city than the solid solution single heavy aging tissue,which has the best resistance to impact bearing ca-pacity.
Ti-1023 titanium alloysolution and agingmechanical propertiesmicrostructureadiabat-ic shear