CHEMICAL PRETREATMENTS OF THE SURFACE OF WC-15wt%Co WITH DIAMOND COATINGS
来源期刊：Acta Metallurgica Sinica2001年第2期
论文作者：S.Liu Y.X.Li D.Q.Yi Z.M.Yu
Key words：chemical pretreatment; cemented carbide; diamond coating;
Abstract: Diamond films were deposited on the cemented carbide WC-15%Co substrates by a hot-filament chemical vapor deposition reactor. The substrate surfaces were chemically pretreated by the following two-step etching method: first using Murakami reagent for 1-3min, and second an HNO3:HCl=1:1 solution for 10-40min. It is indicated that the Co content of the substrate surfaces could be reduced from 15% to 0.81-6.04% within the etching depth of 5-10μm, the surface roughness of the substrates was increased up to Ra=1.0μm, and the substrates hardness was decreased from 89.0 HRA to 83.0HRA after the two-step etching. It is observed that the morphologies of the diamond films on the WC-15%Co substrates emerge in various shapes. The indentation testing shows that the good adhesion between diamond film and the substrate after HF CVD deposition could be obtained.
S.Liu1，Y.X.Li2，D.Q.Yi1，Z.M.Yu1
(1.Department of Materials Science & Engineering, Central South University, Changsha 410083, China;
2.Hunan Yin Zhou Nonferrous Metals Hi-Tech. Ltd. Company, Changsha 410083, China)
Abstract:Diamond films were deposited on the cemented carbide WC-15%Co substrates by a hot-filament chemical vapor deposition reactor. The substrate surfaces were chemically pretreated by the following two-step etching method: first using Murakami reagent for 1-3min, and second an HNO3:HCl=1:1 solution for 10-40min. It is indicated that the Co content of the substrate surfaces could be reduced from 15% to 0.81-6.04% within the etching depth of 5-10μm, the surface roughness of the substrates was increased up to Ra=1.0μm, and the substrates hardness was decreased from 89.0 HRA to 83.0HRA after the two-step etching. It is observed that the morphologies of the diamond films on the WC-15%Co substrates emerge in various shapes. The indentation testing shows that the good adhesion between diamond film and the substrate after HF CVD deposition could be obtained.
Key words:chemical pretreatment; cemented carbide; diamond coating;
【全文内容正在添加中】
