Abstract:

By exploring the oxidation mechanism of titanium alloy during the thermal spray process,its effect on binding properties of the coating/substrate is obtained. Using the method of HVOF,WC coating on titanium alloy surface is prepared under different processing states. Comparing two samples'element contents,microstructures and mechanical properties,the effect of oxidation process on binding properties of titanium alloy/coating during thermal spraying is analysed. EDS analyses show that the sand blasting process has little effect on the oxidation of titanium and it can be ignored basically. By stretching and bending tests we find that oxidation in spraying process has a greater impact on the coating/substrate and leads to different binding properties finally. The results show that the oxidation during spraying process can cause degradation of combination performance of coating/substrate.

Key words: coating/substrate, HOVF, titanium alloy, binding properties, oxidation