TiB_2-Al_2O_3复合陶瓷涂层的制备和性能的研究

Preparation and Performance of TiB_2-Al_2O_3 Composite Ceramic Coating

采用溶胶-凝胶法在铝合金表面制备了TiB2-Al2O3复合陶瓷涂层。用X射线衍射仪(XRD)研究了涂层的物相结构,用扫描电子显微镜(SEM)研究了涂层的组织形貌。并对涂层的硬度和热震性进行了测试。同时研究了稀土金属氧化物CeO2对涂层性能的影响。结果表明:TiB2粉的质量为异丙醇铝质量的24.4%时,在550℃烧结温度下制备的陶瓷涂层致密均匀,而且硬度相对基体可以提高1.4倍,热震次数达到21次。稀土金属氧化物CeO2含量为4%(质量分数)时,涂层性能达到最佳,硬度达到最大值76.4HB,热震次数提高到24次。

TiB2-Al2O3 composite ceramic coating on aluminum alloy substrate was prepared by sol-gel method.The phase composition and surface morphology of coatings were studied by X-ray diffraction（XRD） and scanning electron microscopy（SEM）,respectively,the hardness and thermal shock times were examined as well.The influence of rare earth metal oxide CeO2 on the physical properties of TiB2-Al2O3 composite ceramic coating was studied.The results indicate that： the homogeneous,dense ceramic coating can be prepared when the quality ratio of TiB2 to aluminum is 24.4∶100 and sintered temperature is 550 ℃;its hardness can increase to 1.4 times higher than that of the substrate,and thermal shock times can reach as many as 21 times.When the content of rare earth metal oxide CeO2 is 4%（by mass）,the best physical-property coating can be achieved,its hardness can reach to 76.4HB,and thermal shock times can reach to 24 times.