摘要
利用微弧氧化的方法在-γTiAl合金上制备陶瓷膜,探讨了氧化过程中电流密度与成膜速度的关系。利用扫描电镜研究了氧化膜的表面形态和截面结构,结果表明,氧化膜由三层组成,且氧化膜与基体间有良好的冶金结合;物相分析发现氧化膜中含有金红石、Al2TiO5和SiO2非晶成分,并且物相组成和分布与成膜时间及膜的深度无关;氧化膜的硬度随着氧化时间的增加而增加,极大值出现在距离膜基交界面约10μm附近的氧化膜中。1100℃下的高温氧化实验发现微弧氧化处理后样品的氧化速度只有原始基体材料的1/3,微弧氧化处理后提高了TiAl合金的抗氧化性。
Ceramic coatings on TiAl intermetallic compound were fabricated by AC microarc oxidation.The variation of current density and coating thickness with time was discussed in detail.The morphology,microstructure and microhardness of the coatings were analyzed.The coating consists of three layers and good adhesion between the coating and substrate is observed.XRD analysis indicates that the different layers in the coating mainly consists of Rutile-TiO_2 and Al_2TiO_5.The microhardness of the coating increases with increasing the MAO treating time,and its maximum value in the coating locates at about 10μm from the interface.After isothermal oxidation at 1100℃ for 100h,the formation of Al_2O_3 revealed by XRD enhances the oxidation resistance of TiAl.It is shown that the oxidation resistance of the microarc oxidized sample is about three times higher than that of the substrate.
出处
《材料热处理学报》
EI
CAS
CSCD
北大核心
2006年第5期95-99,共5页
Transactions of Materials and Heat Treatment
基金
国家自然科学基金资助项目(10575011)
北京市科技新星计划项目(9558102500)
北京市科学技术研究院萌芽计划项目
关键词
微弧氧化
TIAL
显微硬度
高温氧化
microarc oxidation
TiAl
microhardness
isothermal oxidation
