Analysis of ignition resistance performance and mechanism of TA7 and TC11 titanium alloys under impact-grinding conditions

A titanium alloy collision friction ignition device was used to conduct collision and continuous friction between TC4 titanium alloy rotating rod and TA7 and other titanium alloy collision samples.Combined with SEM and other microscopic analysis，the anti-ignition performance and products of TA7 and TC11 titanium alloys were studied，and the experimental results under this special friction condition were obtained. The research results show that the friction contact pressure Pf and the combustion chamber pressure P can be effective test parameters to evaluate the titanium alloy impact ignition process. The critical ignition curves of the three titanium alloys drawn based on Pf-P are all linear laws，and the anti-ignition performance is：TC11 > TA11 > TA7. Microscopic analysis of the titanium alloy after impact ignition shows that the combustion reaction zone of the titanium alloy consists of four regions：the combustion product zone （CPZ），the oxide zone （OZ），the heat-affected zone （HAZ），and the friction product zone （FPZ） in total. The multi-layer structure of Al2O3 formed by TC11 after ignition is conducive to blocking the mutual diffusion of Ti，O and other elements，which is the main reason for its superior anti-impact ignition performance.