不同电解液体系中锆合金微弧氧化陶瓷层组织结构和耐磨性能

Microstructure and Wear Resistance of Micro-Arc Oxidized Ceramic Coatings on Zr-4 Alloy in Different Electrolyte Systems

摘要:

采用磷酸盐和硅酸盐体系的电解液分别对锆-4合金进行微弧氧化，对比分析不同体系的电解液中所制备陶瓷层的组织形貌、相结构及耐磨性能。结果表明：在磷酸盐体系电解液中形成的陶瓷层，其致密层厚度约占总膜层的2/3，高于硅酸盐体系的相应值；陶瓷层表面呈典型火山状，比硅酸盐体系的陶瓷层粗糙，但孔洞数量少，内部组织也比硅酸盐体系的陶瓷层致密；两体系电解液中形成的陶瓷层的组成相均主要为t-ZrO2和m-ZrO2，但磷酸盐体系下陶瓷层中m-ZrO2相的质量分数明显要高，而硅酸盐体系中陶瓷层的外侧可能形成硅酸锆。锆合金经微弧氧化处理后，耐磨性能大幅提高，磷酸盐体系中陶瓷层的耐磨性能在总体上优于硅酸盐体系中的陶瓷层

Abstract:

The ceramic coatings on Zr-4 alloy were prepared by micro-arc oxidation in phosphate electrolyte system and silicate electrolyte system respectively. The microstructure, the phase composition and the wear resistance of the ceramic coatings in different electrolyte systems were compared. The results indicate that for the ceramic coating prepared in the phosphate electrolyte, it has thicker dense layers, about 2/3 of the whole layers, than that prepared in the silicate electrolyte; its surface micro-morphology shows typically volcano-shape character, rougher than that prepared in the silicate, but the hole is fewer, and the inner layer is compacter. The ceramic coatings in both electrolyte systems are mainly composed of t-ZrO2 and m-ZrO2, but the mass fraction of m-ZrO2 is higher in phosphate electrolyte and there may be a few zirconium silicate in the outside of the coating in the silicate electrolyte. After the micro-arc oxidation treatment, the wear-resistance of zirconium alloy has a large increase and the wear-resistance of the coating prepared in the phosphate electrolyte is superior to that prepared in the silicate electrolyte