Research And Application Of Vitrified Bonded Diamond Grinding Tool

Vitrified bond diamond grinding tools have been widely used in the fields of modern material processing especially hard brittle materials because of its grinding efficiency, high grinding precision, great grinding ratio, low grinding temperature, long wheel life, acidproof alkali, good self sharpness. This paper intends to research the low temperature vitrified bond, diamond coated with different metals, pressure molding process, sintering process and grinding application. We can conclude as follows:1) Developing HO vitrified bond, which have a wide range of sintering and whose melting point is about650℃. The bending strength of vitrified bond diamond grinding tool can go up to90.08MPa in sintering temperature of735℃. Drawing up sintering process for HO vitrified bond. There are microcrystalline phase of spodumene(LiAlSi2O6)in abrasive which can increase strength of tools using HO vitrified bond.2) Diamonds coated with different metals of copper, nickel and titanium are used as abrasive particle in making vitrified abrasive tools. The strength decrease due to metal oxidation reaction in sintering process.3) Using resin liquid as wetting agent in4wt%～5wt%adding to forming materials can result in the best formability, green and finished abrasive segments bending strength. The bending strength of green can reach as high as8.9MPa and the bending strength of abrasive samples can go up to91.28MPa.4) The roughness is0.5μm～0.9μm grinding cemented carbide of YG8when we used abrasive with diamond of140/170mesh size. The roughness is0.1μm～0.3μm using abrasive with diamond of270/325mesh size. And grinding efficiency is higher, but the surface roughness is poorer using vitrified bond abrasive than using resin bond grinding wheel. Vitrified bond grinding wheels can grind1233pieces of1304PCD and have high grinding efficiency. Diamond abrasives with HO vitrified bond have a better performance than domestic similar products considering the wearability, sharpness and workpiece quality after grinding.The vitrified bond diamond grinding tools have a better performance than resin emery wheel:(1) vitrified bond wheel has higher grinding efficiency;(2) using large amount of feed is easier with vitrified bond abrasive than resin bond wheel grinding cemented carbide;(3) vitrified bond abrasive does not need truing and dressing while resin abrasive must be dressed every once in a while;(4) The grinding accuracy is higher using vitrified bond abrasive compared with resin grinding wheel.