In-situ measurement of the temperature inside the grinding wheel

During the grinding process, high temperatures are generated in the contact area through shearing and friction between the tool and the workpiece. These can damage the workpiece or alter its properties, e. g. introduce tensile residual stresses or change the microstructure through phase transformation. Therefore it is crucial to study the energy balance and especially the energy distribution between the grinding tool and the workpiece. Grinding wheels with high thermal conductivity have the potential to absorb more energy and shift the heat distribution away from the workpiece and towards the tool. In order to investigate the influence of the grinding wheel properties on the heat distribution, this study presents an approach to measure the temperature inside the grinding wheel. The measuring unit for the grinding wheel is clamped on the tool spindle in front of the grinding wheel and thermocouples are inserted into the bond of the grinding wheel. With this method, the energy balance of grinding wheels with sintered bronze bonding and different concentrations of CBN grains was investigated. It is shown, that the grinding wheel takes up more heat at higher grain concentrations due to the increased thermal conductivity of the abrasive layer.