A way to fabricate an Al-Si coating on the surface of a Ti alloy and its high-temperature oxidation resistance

An Al-Si fusing coating was successfully produced by low-oxygen pressure high-temperature fusing technology for improvement of the high-temperature oxidation resistance of Ti alloys. Compared with other technologies, this technology was correspondingly simple without long-term treatment and the concentrations of Al and Si in the fusing coating could be controlled by adjusting the powders' mixing ratio. It is verified by XRD that the Al-Si fusing coating is mainly composed of Al, Si, Ti₅Si₃, and TiAl₃ phases. Cyclic oxidation tests at 1073 K for 105 h in air reveals that the mass gain of the uncoated Ti alloy keeps rapidly increasing during oxidation, while the Al-Si fusing coating obeys a parabolic law and remarkably improves the oxidation resistance.