沉积温度对硬质合金金刚石涂层附着力影响的研究

采用压痕实验、扫描电镜与激光Raman光谱分析,实验研究了酸浸硬质合金基底上金刚石涂层的附着力随沉积温度的变化.结果表明,涂层质量随沉积温度降低而显著恶化,涂层应力则随沉积温度提高而上升.从提高涂层附着力的角度考虑,存在一个最佳沉积温度.在较低的沉积温度下,涂层自身的质量较低、力学性能较差,在载荷作用下易于破坏.提高沉积温度,涂层自身的质量可得到改善,但基底中的钴向基底表面扩散的倾向加大,而且热应力增大,会严重降低涂层与基底的附着力.除硬质合金基底的预处理工艺外,沉积工艺对金刚石涂层的组织、性能以及附着力均有重要影响.

Influence of Deposition Temperature on Adhesion of Diamond Coatings on Cemented Carbide Cutting Tools

By combining indentation, SEM as well as Raman spectroscopy techniques, the dependence of adhesion of diamond coatings on cemented carbide cutting tools on deposition temperatures was investigated. Experimental results show that, at low deposition temperatures, both the quality and mechanical properties of diamond coatings are very poor. The coating quality improves when the deposition temperature increases. But the diffusion trend of cobalt atoms from the substrate interior to the surface and thermal stress in the coatings increase with the deposition temperature, both of them will decrease the adhesion of the diamond coatings. All these results indicate that, in addition to a proper pretreatment of the substrates, diamond deposition conditions have important influences on microstructure, mechanical property and adhesion of diamond coatings.