The oxidation behavior and mechanical performance of Ti60 alloy with enamel coating

In the present paper, the influence of enamel coating, compared to the traditional TiAlCr coating, on oxidation behavior and oxygen contamination of Ti60 alloy at 700 and 800 °C was studied. A continuous protective alumina scale formed on TiAlCr coating during oxidation at the two temperatures; but a rather heavy interdiffusion layer appeared at the interface of TiAlCr/Ti60 during oxidation at 800 °C. The uniform and dense enamel coating could provide excellent protectiveness to Ti60 due to its thermal chemical stability and good compatibility in terms of thermal expansion coefficient to the substrate Ti60 alloy. According to the microhardness measurement results, there exists a layer of contamination of about 30 μm into the alloy after the enamel was vitrified for 30 min at 900 °C in air; but the depth of oxygen contamination into the alloy changed little after oxidation for 1000 h at 600 °C. The strength and the elongation at ambient temperature of Ti60 alloy with enamel coating decreased about 7.4% and 3.4% in comparison to the original bare alloy, respectively. From the results, the enamel coating could protect Ti60 alloy from oxidation and oxygen embrittlement.