Co evolutions for WC-Co with different Co contents during pretreatment and HFCVD diamond film growth processes

金刚石形核及薄膜生长过程中不同钴含量WC-Co基体中的钴演变（英文）

Systematical researches were accomplished on WC-Co with different Co contents(6%,10%and 12%,mass fraction).Based on the XPS and EDX,from orthogonal pretreatment experiments,it is indicated that the acid concentration,the time of the acid pretreatment and the original Co content have significant influences on the Co-removal depth(D).Moreover,the specimen temperature,original Co content and Co-removal depth dependences of the Co evolution in nucleation,heating(in pure H2 atmosphere)and growth experiments were discussed,and mechanisms of Co evolutions were summarized,providing sufficient theoretical bases for the deposition of high-quality diamond films on WC-Co substrates,especially Co-rich WC-Co substrates.It is proven that the Co-rich substrate often presents rapid Co diffusion.The high substrate temperature can promote the Co diffusion in the pretreated substrate,while acts as a Co-etching process for the untreated substrates.It is finally found that the appropriate Co-removal depth for the WC-12%Co substrate is 8-9μm.

在具有不同钴含量(6%,10%和12%,质量分数)的硬质合金样品上进行系统试验。基于XPS和EDX检测方法,采用正交试验方法证明了酸浓度、酸处理时间和原始钴含量对去钴深度有显著影响。在此基础上,研究形核、纯氢气氛围加热及生长试验条件下基体温度、原始钴含量及去钴深度对钴演变的影响规律。得到金刚石薄膜涂层器件制备全过程中钴元素的演变机理,为WC-Co基体表面、尤其是高钴含量WC-Co基体表面高质量金刚石薄膜的沉积提供理论依据。结果表明:高钴基体通常表现出较快的钴扩散速度;较高的基体温度会促进预处理基体中的钴扩散,但是在未处理基体中却表现出钴刻蚀作用;对于WC-12%Co基体,较为合适的预处理深度为8-9μm。