【摘要】 采用有限元方法分析了硬质合金氮化钛涂层的热残余应力,试样采用圆柱体状的轴对称几何模型和自由边界条件,分析了涂层厚度、基体参数和过渡层对残余热应力的影响。计算表明:TiN涂层中出现较大的拉应力(1GPa以上),而硬质合金基体中出现较大的压应力(-0.8GPa左右)。涂层中的拉应力随硬质合金基体中钴的质量分数和涂层厚度的增加而明显减小,因此通过增加基体中的钴的质量分数和涂层厚度可以减小涂层中的拉应力。当采用TiC过渡层时,涂层应力可以减小25%,且采用TiCN梯度过渡层时效果更好。更多还原

【Abstract】 Thermal stresses in TiN coatings deposited onto cemented carbide substrates are calculated by using the finite element method.The thermo-elastic stress fields for some coating-substrate axisymmetric geometries are presented.Effect of different coating thickness and substrate properties on residual stress field is considered.The numerical results show that high tensile stress(above 1 GPa) occurs in the TiN coating and high compressive stress(about-0.8 GPa) occurs in the substrate.Tensile stress in coating layer increases with the increasing coating thickness and cobalt content of cemented carbides substrate.The tensile stress can be decreased by decreasing coating thickness and cobalt content of cemented carbides.Thermal residual stress decreases by 25% with TiC interlayer and the effect is better with graded TiCN interlayer than TiC.更多还原