(南京航空航天大學 機電學院 江蘇省精密與微細制造技術重點實驗室，南京 210016)
摘 要: 采用Ni-Cr合金活性釬料，在高真空爐中實現(xiàn)金剛石與鋼基體牢固的釬焊連接。借助掃描電鏡、能譜分析儀和X射線衍射儀闡述真空釬焊金剛石的釬焊機理和界面特征，分析釬焊金剛石圓鋸片在干式加工鑄鐵過程中磨粒的磨損特性。結(jié)果表明：在鑄鐵管加工方面，釬焊金剛石圓鋸片表現(xiàn)出優(yōu)越的高效切割性能，磨粒磨損主要以破碎為主，磨削高溫引起切屑粘附在破碎磨粒表面；揭示在鑄鐵干式加工過程中金剛石磨粒表面出現(xiàn)輕微的石墨化磨損等現(xiàn)象；實驗表明磨粒的強度依然能滿足加工要求。研制出適用鑄鐵材料高效加工用的高鋒利度、高強度、安全的釬焊金剛石切割片。
關鍵字: 金剛石圓鋸片；鑄鐵管；真空釬焊；磨損機理；干式加工
（Jiangsu Key Laboratory of Precision and Micro-manufacturing Technology,
College of Mechanical and Electrical Engineering,
Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China）
Abstract:Diamond grains were brazed onto steel (0.45%C) matrix in high vacuum furnace using Ni-Cr active powder filler alloy. Scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffracometry (XRD) techniques were applied to investigate the interface characteristics of brazing diamond abrasive crystals to steel substrate and the wear characteristics in dry cutting cast iron process. The results show that the brazing diamond saws have obvious advantages in terms of high efficiency cutting cast iron. The main wear of the grains is grits fracture from the brazed combined zone. The iron chips are adhered to the surface of the broken grains at high grinding temperature. The graphitization of diamond grits slightly occurred and the diamond strength is enough to meet the requirements of machining process when dry-cutting cast iron. The super sharp, high strength and safety brazed diamond saw was developed for the high efficiency machining cast iron materials.
Key words: diamond saws; cast iron pipe; vacuum brazing; wear mechanism; dry-cutting
