金刚石薄膜在硬质合金基体上的生长及附着强度研究

硬质合金是制作金刚石薄膜涂层刀具的重要基体材料,金刚石薄膜在硬质合金基体上的成核、生长及界面特征直接影响其附着强度.本文通过扫描电镜、X射线衍射分析、X射线光电子谱(XPS)及断续切削实验,研究了硬质合金基体含Co量对金刚石薄膜成核、生长及附着强度的影响.研究结果表明,经酸洗处理后,硬质合金基体含Co量对金刚石薄膜成核、生长没有太大影响.但对其附着强度有很大影响.含Co量越高,附着强度越低.酸腐蚀去Co处理后基体表面变得疏松、不连续非金刚石碳界面的存在及热膨胀系数较大是含Co量较高时,附着强度下降的主要原因.

Study on the Growth and Adhesive Strength of Diamond Film on the Substrate of Carbide

Carbide is an important kind of substrate material for making diamond film coated tools. The forming nucleation, the growth and interface characteristics of diamond film on carbide substrate affect its adhesive strength directly. This paper studies the influences of Co content of carbide substrate on the forming nucleation, the growth and adhesive strength of diamond film by scanning electron microscopy, X-ray diffraction analysis, X-ray photo electron spectrum (XPS) and interrupted cutting experiment.The results show that the influence of Co content of carbide substrate on the forming nucleation and growth of diamond film is not great after acid picking treatment, but the influence on adhesive strength is too much. The higher the Co content, the lower the adhesive strength is. When the Co content is fairly high, the main factors of falling adhesive strength are the loose of substrate surface after removing Co by acid corrosion, the existence of discontinuous crusher carbon interface and larger thermal expansion coefficient.