ENERGY PARTITION TO THE WORKPIECE FOR GRINDING WITH ALUMINUM-OXIDE AND CBN ABRASIVE WHEELS

An experimental investigation is reported of the energy partition to t he workpiece for grinding of steels with aluminum oxide and cubic boro n nitride (CBN) abrasive wheels. The energy input to the workpiece was obtained by measuring the temperature distribution in the workpiece u sing an embedded thermocouple technique and matching the results with analytically computed values. It was found that 60-75 percent of the g rinding energy is transported to the workpiece as heat with an aluminu m oxide abrasive wheel, as compared to only about 20 percent with CBN wheels. An analysis of the results indicates that the much lower energ y partition to the workpiece with CBN can be attributed to its very hi gh thermal conductivity whereby a significant portion of the grinding heat is transported to the abrasive instead of to the workpiece. The m uch lower energy partition to the workpiece with CBN wheels results in much lower grinding temperatures and a greatly reduced tendency for t hermal damage to the workpiece.