关键词: 金刚石, 沉积处理, 感应钎焊, 锋利性, 把持强度

Abstract:

Diamond grits were deposited by hot filament chemical vapor deposition (HFCVD) and they were used to fabricate the brazed diamond tools by induction brazing. The gas ratio (H2/CH4) used was 100∶1.5(standard cubic-centimetres per minute), the total gas pressure was maintained at about 2.0 kPa, and the substrate temperature was heated to 700℃ for 45 minutes during HFCVD. As a result, amorphous carbon film is deposited on the diamond surface. The diamond edges exposed out of the filler alloy keeps good sharpness after induction brazing of HFCVD deposited diamond. Chromium-carbides with uniform porosity and irregular shapes were formed on the diamond grits immersed into the brazing filler alloy. The liquid brazing filler metal filled in porosity can enhance the bonding strength between the brazing filler metal and the diamond grits. The heavy-load grinding tests of the brazed diamond wheels fabricated by three kinds of diamond grits show that there is a low percentage of pullout from matrix and whole grain fracture for the deposited diamond grits brazed by induction heating. 

Key words: diamond, deposition treatment, induction brazing, sharpness, bonding strength