Evaluation of brazed monolayer CBN grinding wheel on high-speed steel (HSS)

Abstract

Shaping and forming of high-speed steel (HSS) tool with complicated geometry has been a challenge for the cutting tool industry. HSS grades generally display high hardness at high temperature and high wear resistance due to its constituent elements like a high amount of tungsten with the addition of chromium, vanadium and cobalt. HSS being used extensively in the manufacturing industry for machining difficult-cut-materials due to its high hardness and abrasion resistance. CBN grinding wheel is being used extensively for shaping the HSS. In this work, cBN brazed wheel with monolayer configuration is being used to grind HSS. Usually, reasonably uniform grit distribution, adequate spacing between the grits, 50-70% grit protrusion over the brazed surface and strong chemical bond strength are key features of brazed CBN wheel to perform satisfactorily. In the current investigation, the brazed CBN wheel showed limitations of its capability while grinding HSS in dry condition. The high chip load due to adverse grinding combinations, high attrition wear of grit due to its interaction with constituent elements like tungsten, chromium, vanadium and cobalt, fracturing and pull out of the grits are the limitation of the brazed wheel. The paper also concluded with facts to overcome limitations of brazed CBN wheel.