硬质合金表面去钴和脱碳对金刚石薄膜粘结性能的影响

Effect on the Adhesion of CVD Diamond Films to Cemented Carbide Substrate by Acid Etching and Decarburization Method

金刚石涂层的粘结性能是影响CVD金刚石薄膜涂层刀具使用寿命的关键因素。本文分别对硬质合金 (YG6 )表面进行酸蚀去钴和原位脱碳两种不同的预处理后 ,在热丝CVD系统中沉积金刚石薄膜 ,运用压痕试验评价金刚石薄膜与硬质合金基体的粘结性能。结果表明 ,经过原位脱碳预处理的硬质合金表面上金刚石涂层的粘结性能比酸蚀去钴法提高了近一倍 ;同时分析了硬质合金表面酸蚀去钴对金刚石薄膜粘结性能的影响及其剥离机制 。

The adhesive strength of diamond thin films is a key factor to affect the lifespan of diamond-coated tools. Prior to deposition of diamond films in hot filament CVD system, the substrates were pretreated by acid etching and in-situ decarburization respectively. Indentation tests were performed to evaluate adhesive strength of diamond films to the substrate. The results show that the adhesion by in-situ decarburization is nearly two times stronger than that of the acid etching. At the same time, the cause of adhesive strength by acid etching and its delamination mechanism were analyzed, and the chemical mechanism of in-situ decarburization was discussed in detail.