Wear characteristics of brazing diamond abrasive wheel on high efficiency grinding ferrous metals

Abstract

A kind of diamond abrasive grinding wheel was brazed in high vacuum furnace using Ni–Cr–P–Si active powder filler alloys. Scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), Raman spectra and X-ray diffraction (XRD) technique analysis were applied to investigate the wear characteristics of brazing abrasive grinding wheel during the process of dry cutting ferrous metal and the interface characteristics of brazing diamond grains to steel substrate. The reaction products such as Cr7C3 and Cr3C2 carbides with columnar shape were formed toward around the diamond brazed interface. The results showed that diamond brazing abrasive wheel had an advantage in terms of more high efficiency and safety than resin grinding wheel during the process on cutting ferrous metals. The main tool wear model was abrasive grains broken, fracture and corrosion which were near the brazed interface. It revealed that the cutting chips were adhered to the surface of broken grains and covered the abrasive grits during the cutting process where arising high temperature on the grinding arc zone. Results proved that the graphitization phenomenon of diamond grits was slightly occurred and the diamond bonding strength was strong enough to meet the requirements of high efficiency and heavy load machining on dry cutting cast iron. The experiment also demonstrated that a kind of safety, high strength and super sharp diamond abrasive wheel could raise machining efficiency on cutting ferrous metal materials.