铜置换去钴法制备金刚石薄膜研究

Study of Diamond Deposition on Cemented Carbide Pretreated by Copper Sulfate Solution

CVD金刚石涂层刀具一直是国内外研究的热点,目前对于含钴量6%的硬质合金涂层刀具研究较多。使用硫酸铜溶液处理含钴量10%的高钴硬质合金刀片,在超声振动条件下置换出其表面的钴,并采用热丝CVD法沉积金刚石薄膜。研究了硫酸铜溶液浓度对硬质合金表面形貌的影响,优选出适合浓度的硫酸铜溶液并优化预处理工艺,利用SEM,XRD,Raman等手段表征薄膜品质。结果表明,置换出的金属铜层降低了钴对金刚石生长的影响,提高了形核密度以及金刚石膜的生长速率,金刚石纯度较高。

CVD diamond coating tools are research hotspots both at home and abroad. At present, the attention is most focused on the study of the WC with low content of cobalt （6 wt% Co content）. In this paper, the copper sulfate solution is used to freat the ce- mented carbide inserts（ with ]0 wt% Co content） and to replace cobalt on surface by Cu under the ultrasonic vibration condition, then diamond thin films are deposited on the carbide inserts by hot filament chemical vapor deposition process. The effect of the CuSO4 concentration on the surface morphology of the cemented carbide is studied, the proper CuSO4 concentration is selected and the process of the pretreatment is optimized. The scanning electron microscope, X-ray diffraction and Raman scattering spectroscopy. are used to characterize the film quality.The results show that the Cu interlayer decreases the catalytic effect of cobalt and increases the nucleation density,film growing rate and the purity of the diamond film.