Preparation and Grinding Performance of Polyimide Resin Bonded Cubic Boron Nitride Composite Grinding Wheels

A polyimide resin (PI) bonded cubic boron nitride (CBN) abrasive grain grinding wheel was prepared by hot-pressing curing and forming and subsequent thermal treatment. The PI resin curing mechanism, the manufacturing process and grinding performance of the PI resin/CBN wheel were investigated by differential scanning calorimeter and thermogravimetry analysis, infrared spectroscopy, scanning electron microscopy, mechanical property test and grinding experiments. Results show that there were two exothermic peaks of 140 ℃ and 235 ℃ corresponding to chain and a cross-linking polymerization reaction, respectively in the PI resin curing process. Surface roughness of 0.19 μm and grinding ratio of 775 were obtained when the PI resin bonded CBN wheel grinded the hardened steel 45. The PI resin bonded CBN wheel exhibited better durability than the phenolic resin bonded CBN grinding wheel under the same grinding condition.