Ignition resistance and mechanisms of TC11 titanium alloys with flame retardant coating

Abstract

The effect of YSZ+NiCrAl-B.e composite coating on the ignition resistance of TC11 titanium alloy was studied by using the method of friction in oxygen-enriched atmosphere. Combining friction and wear analysis and unsteady heat conduction calculation, the fireproof mechanism of the composite coating was discussed. The results show that the YSZ+NiCrAl-B.e composite coating significantly improves the ignition resistance of the titanium alloy, and its critical ignition oxygen concentration is about 2.3 times than that of the bare titanium alloy. The friction property of the friction pair composed of the titanium alloy and the composite coating is higher than that of the friction pair composed of titanium and titanium alloy; And the effect of NiCrAl-B.e layer on the ignition resistance of the titanium alloy is not obvious. In the process of friction ignition, the YSZ layer can significantly reduce the temperature rise of the titanium alloy substrate though preventing the rapid heat transfer, delaying the ignition of the titanium alloy. In this sense, the YSZ layer is the flame retardant layer in the coating system, and heat barrier is the main fireproof mechanism.