金刚石薄膜与 WC-Co 硬质合金的附着性研究

以甲烷和氢气为气源，用热丝ＣＶＤ法，在ＷＣ－６％Ｃｏ的硬质合金基体上沉积金刚石薄膜。研究了基体表面经抛光、腐蚀、脱碳及镀中间层等不同的预处理对金刚石薄膜与基体的附着性的影响。试验结果表明：基体表面经抛光、腐蚀再经脱碳或镀ＴｉＮ中间层，可改善和提高附着性，金刚石薄膜的形核率和沉积速率有所降低；基体表面只经抛光、腐蚀预处理，金刚石薄膜的形核率和沉积速率较高，结晶性好，但附着性较差；采用分段沉积，可以提高金刚石薄膜的附着性。

Investigation on the Adhesion between Diamond Films and WC Co Cementend Carbides

Diamond films have been synthesized on WC 6%C O cemented carbide inserts by hot filament chemical vapor deposition. The influence of various pretreatment processes such as mechanically polishing, chemically etching, decarbonizing and precoating intemediate layer on the adhesive strength was investigated by using indentation. The experimental results show that the adhesive strength can be enhanced by the pretreatment process of polishing etching decarbonizing or precoating TiN intermediate layer. However, for the in situ plasma decarbonization owing to carbonization the concentration of nucleation particles on the substrate surface decreased during the initial deposition, which leads to a reduction in the nucleation density. The nucleation density and growth rate are high, but the adhesion is poor when only polishing etching pretreatment for the WC C O substrates.Moreover, the adhdsive strength of diamond films and the cemented carbide inserts can be strongly enhanced by intermittent deposition.