【摘要】 为提高陶瓷材料表面的硬度和韧性,热压烧结制备了Al2O3–(W,Ti)C/Al2O3–TiC对称型叠层陶瓷材料。研究了该叠层材料的层厚比和层数对材料表层的硬度、断裂韧性的影响。此外,通过压痕裂纹法的测量和有限元计算均可以得到叠层陶瓷材料表面层的残余应力值,两种方法获得的残余应力值符合得很好。通过有限元计算还可以得到叠层陶瓷材料不同层内的残余应力分布特征。对比实验表明:叠层陶瓷材料表面层较之相应单一材料而言,具有更高的硬度和断裂韧性。叠层陶瓷材料中残余压应力的存在,是叠层陶瓷材料表面层具有高硬度、高韧性的原因。而且通过改变叠层材料的层厚比和层数可改变叠层材料残余应力的分布。更多还原

【Abstract】 In order to increase the hardness and toughness of the surface of ceramics,Al2O3–(W,Ti)C/Al2O3–TiC symmetric laminated materials were prepared by hot pressing.The effects of layer thickness ratio and layer number on the hardness and toughness of the surface of laminated ceramic materials were discussed.The residual stresses developed in the ceramic layers were measured by indentation technique.The obtained residual stress values are in good agreement with residual stresses calculated by the finite element method(FEM).The residual stress distribution in the different layers were also assessed by the FEM.Comparison of the FEM analysis with the experimental results shows that both the hardness and toughness of laminated ceramic materials are better than those of simple materials.The compressive residual stresses on the surface of the composite are the main reason for the improved hardness and toughness of laminated ceramic materials.And the residual stresses can be controlled by changing the relative layer thickness ratio and layer number of laminated ceramic materials.更多还原