船用Ti-6Al-3Nb-2Zr合金的微弧氧化陶瓷膜

Micro-arc oxidation ceramic coatings formed on marine Ti-6Al-3Nb-2Zr alloy

采用微弧氧化技术,在磷酸盐溶液体系中在船用Ti-6Al-3Nb-2Zr合金表面制备陶瓷膜层。利用扫描电镜、光学显微镜、X射线衍射仪和显微硬度计对陶瓷膜的表面和截面形貌、氧化层厚度、相结构以及显微硬度进行观察测试,用电子万能材料试验机和数字万用表研究膜层的结合强度和绝缘性,并用MMS-1G高温高速销盘摩擦磨损试验机和YWX/Q-750盐雾试验机考察膜层的摩擦学性能和腐蚀性能。结果表明:膜层厚度可达到20μm以上,陶瓷膜主要由金红石TiO_2相和锐钛矿TiO_2相构成,膜层与基体的结合强度达到30MPa以上,膜层绝缘性和耐蚀性良好,耐磨性得到明显改善,膜层的磨损机制表现为轻微的磨粒磨损与粘着磨损,且以磨粒磨损为主。

The ceramic oxide coatings were formed on marine Ti-6Al-3Nb-2Zr alloys surface by micro-arc oxidation（MAO） in phosphatic aqueous solution. The surface and sectional microstructures, oxide layer thickness, phase composition and microhardness were characterized by SEM, optical microscopy and XRD. The bonding strength, insulating performance, tribological properties and corrosion resistance of the coatings were also investigated. The results indicate that the oxide film with thickness of about 20 μm as compose mainly by rutile and anatase TiO2 phases. The bonding strength between the Ti-6Al-3Nb-2Zr substrate and the film is over 30 MPa. The ceramic coating shows good insulation, abrasion and excellent corrosion character. The wear mechanism of the microarc oxidation ceramic coating is characterized by slight abrasive wear and adhesive wear, and the abrasive wear is the main mechanism.