Effect of Heat Treatment on Characteristics of Coating Formed on Beta Titanium Alloy by Micro-arc Oxidation

Abstract:

The phase composition and resistivity of Ti-3.5Al-5Mo-6V-3Cr-2Sn-0.5Fe alloy undergone with different heat treatment process were studied, and the effects of heat treatment on thickness, roughness, micro morphology and phase composition of micro-arc oxidation coating were analyzed. The results show that the phase composition of Ti-3.5Al-5Mo-6V-3Cr-2Sn-0.5Fe alloy is changed by different heat treatment. The resistivity of alloy is slight decrease after heat treatment. With the solidSsolutionSheat treatment of 850 ℃, the minimum thickness and roughness of the micro-arc oxidation coating is 48.3 μm and 7.45μm which is obtained respectively. By the observation of morphology of oxidation coating, the crack is less and coating is compact with 750 ℃ and 850℃ solid solution heat treatment. XRD analysis shows that micro-arc oxidation coating is composed of anatase TiO₂ and rutile TiO₂.