目的 改善硬质合金表面金刚石薄膜的结合力。方法 采用热丝CVD法在硬质合金基体上制备金刚石薄膜，研究对比喷砂+一步法、喷砂+两步法、AlCrN过渡层和传统两步法这四种预处理对金刚石薄膜质量及其结合性能的影响。对预处理后硬质合金基体表面的形貌和粗糙度进行分析，并通过扫描电子显微镜、X射线衍射、拉曼光谱及洛氏硬度计表征金刚石薄膜的形貌、结构及性能。结果 喷砂有利于在基体表面获得均匀分布的凹坑，提高金刚石的形核密度及均匀性，尤其改善了金刚石颗粒的团聚现象。AlCrN过渡层虽然表面粗糙度不高，但有大量的凸起颗粒，提供了极佳的形核点，也在一定程度上优于传统两步法的表面金刚石形核密度。在金刚石薄膜沉积参数不变的前提下，传统两步法预处理获得的涂层结合力为HF4级，喷砂结合一步法和两步法获得的结合力分别达到了HF3级和HF1级，但AlCrN过渡层的结合力表现较差。结论 AlCrN过渡层能阻挡Co的扩散，提高了金刚石的纯度，但金刚石膜的内应力较大，结合力差。喷砂和刻蚀复合预处理不仅能提高金刚石的结晶质量和纯度，金刚石薄膜的结合力也得到改善。

The work aims to improve adhesion of diamond films on cemented carbides. The diamond films were deposited on cemented carbide substrates in the method of hot filament CVD. The effects of four pretreatment methods, i.e., sandblasting plus one-step etching, sandblasting plus two-steps etching, AlCrN transition layer and traditional two-steps etching method, on quality and adhesion properties of the diamond films were investigated. Morphology and roughness of the pretreated cemented carbide substrates were analyzed. Morphology, structure and properties of the diamond films were characterized with field emission scanning electron microscopy (FESEM), X-ray diffractometer (XRD), Raman spectroscopy and Rockwell hardness tester. Sandblasting was beneficial to uniformly distributed dimples on the substrates, and nucleation density and uniformity of diamond, and especially agglomeration of diamond particles. Although the surface roughness of AlCrN transition layer was not high, a large number of convex particles provided excellent nucleation sites. Nucleation density of diamond treated in this way was superior to that treated in traditional two-steps method to some extent. Provided with the same deposition parameters of diamond films, the adhesion of diamond films pretreated in the methods of two-steps etching, sandblasting plus one-step etching and sandblasting plus two-steps etching was class HF4, HF3 and HF1, respectively, while the adhesion of AlCrN transition layer was poor. AlCrN transition layer can prevent outward diffusion of Co and improve purity of diamond, but the diamond films exhibit high internal stress and poor adhesion. The combined pretreatment of sandblasting and etching not only improve crystalline quality and purity of diamond, but also enhance adhesion of diamond films.