材料工程Issue(11)：89-96,8.
直流电化学两步处理精磨硬质合金表面对CVD金刚石涂层的影响
Effects of Two-step DC Electrochemical Pretreatment Method on Diamond Coatings on Fine Grinding Cemented Carbide Surfaces
摘要
Abstract
Due to the fine grinding WC-Co substrate which has been polished to provide a keen/cutting edge must be pretreated before depositing CVD diamond coating. However, conventional chemical etching methods may have the drawbacks of difficulties in corrosion efficiency and process repeatability for its large-scale applications . An investigation had been carried out to study the influence of the two-step DC electrochemical pretreatment (firstly using DC electrolytic etching, and then using acid etching) on the fine grinding cemented carbide substrates and diamond coatings by means of Scanning E-lectron Microscope (SEM), profilometer, Atom Absorption Spectrometry (AAS),Energy dispersive X-ray diffraction analysis (EDXA) and Rockwell hardness tester respectively. The results showed that the two-step DC electrochemical pretreatment method can effectively remove the "skin" of grinding substrates surface and reduce the Co content. Through changing the electrolytic time,the relationship amongst substrate surface roughness, the substrate surface Co concentration removal and the hardness of substrate surface after Co removed are balanced, and effectively control CVD diamond coating from microcrystalline cubic-octahedron to cauliflower type nanocluster transformation process, which has a good controllability. According to the substrate/coating hardness, coating quality and coating adhesion strength testing results, optimized the best process parameters of the two-step DC electrochemical pretreatment method at fine grinding cemented carbide substrates, which firstly using DC (direct current) 1A electrolytic etching for 5 minutes in 10% sodium hydroxide (NaOH) solution, and thenetched in an aqua regia CHNO3:3HC1 : H2O=1 :1: 1) solution for 90 seconds.关键词
直流电化学两步处理法/金刚石涂层/化学气相沉积/精磨硬质合金Key words
two-step DC electrochemical pretreatment method/diamond coating/chemical vapor deposition/ fine grinding cemented carbide分类
矿业与冶金引用本文复制引用
张湘辉,汪灵,龙剑平,朱必武,陈伟,冯艳华..直流电化学两步处理精磨硬质合金表面对CVD金刚石涂层的影响[J].材料工程,2011,(11):89-96,8.基金项目
国家自然科学基金项目(50974025,40572030) （50974025,40572030）
四川省科技厅重点科技攻关项目(05GG021-001) （05GG021-001）
四川省教育厅自然科学科研项目(2003A142,07ZB009) （2003A142,07ZB009）
成都理工大学研究基金项目(2005GY02) （2005GY02）
