Influence of the Abrasive Grain on the Surface Integrity of High Speed Steel

Summary

The surface integrity of high-speed steels ground with aluminium oxide and cubic boron nitride abrasive is examined. Experimental tests demonstrate that the particular type of abrasive used in grinding is one of the most important factors influencing the surface integrity of high-speed steels. Even under moderate feedrate conditions, aluminium oxide wheels create disturbed material zones which differ in microstructure and hardness from the parent metal. There is significantly less tendency to disrupt the work-piece when using cubic boron nitride abrasive under similar grinding conditions. The results of these metallurgical studies are substantiated by drill-life studies where drills pointed with CBN abrasive exhibited better tool-life than drills similarly ground with aluminium oxide.