| Although titanium alloy has excellent performance at normal temperature, the resistance to oxidation and erosion is not ideal. Because of the noncrystallic strcture, enamel has eminent property in these aspect ,so can protect alloy. Due to its special electronic structure and high melting point of RE(rare earth) has been applied widely in industry to improve the mechanical property of enamel recently years. These paper study the effect of RE on the wearing. quality and tensil strength when they are added to the enamel.Prefabricating enamel frit is mainly used such normal methods as dipping and spray coating. But, the thickness of the coating obtained is not uniform. Compared with porcelain dipping and spray coating, electrophoretic deposition (EPD) has great advantages. For example, there is no limitation in the shape of matrix and the thickness of coating is even.A kind of electrophoretic solution adapted to prefabricating enamel on Ti60 alloy was studied. The processing parameters were optimized. The various factors affected deposition qulity were discussed. The kinetics of EPD was investigated and the process of speed controlling EPD was determined. The optimal processing parameters of prefabricating enamel coating on titanium alloy by electrophoretic deposition were given.Sintering technique of enamel coating were studied. Microstructure and phase composition of enamel coating was observed .At the same time, the ordinary enamel coat and RE enamel coat were compared to study their character in oxidation, erosion, wearing and tensile strength.Research shows that the optimal processing parameters are as follows: The concentration of enamel-eletrophoretic solution is 150-200g/L, the voltage is 3-5V, thetime of EPD is 3-5s, the die opening is 1.5-2.5cm, sintering temperature is at 850°C - 900 °C and time is 20- 40min.The cross section morphology of the coating observed by SEM/EDX indicated that a tight bonding between the matrix and coating and a high density of film were obtained.There is an obvious oxide layer on the surface of Ti60 alloy after oxided at 700°C in air, and the oxidation kinetics of Ti60 alloy follows a parabolic curve. Enamel coating whether there was RE or not markedly improved the oxidation resistance of the alloy at 700 °C in air, since the coating possesses a good thermo-chemical stability and a thermal expansion coefficient matched with that of Ti60 alloy.The corrosion kinetics of Ti60 alloy follows parabolic curve in both condition of brushing salt and melting salt. Enamel coating has shown a good corrosion resistance whether there was RE or not.The ordinary enamel coat exihibit good abrasion resistance compared with metrix alloy. The wearing failure of enamel coat took on brittleness spalling character which originated from crack generated during slid. The added RE can ameliorate this situation.The high melting point of RE can nucleate early and so will control the diffusion of oxygen into metrix.From the tensil fracture morphology ,a narrower oxygen brittleness layer was observed.
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