Grinding Temperature Measurements in MgO-PSZ Using Infrared Spectrometry

Introduction When the grinding wheel specifications are properly chosen, a SiC grinding wheel performs remarkably well for grinding partially stabilized MgO-ZrO2 ceramics (MgO-PSZ). Rather surprisingly, the highest Gratios are obtained at higher grinding rates for the SiC wheel. This, and the fact that SiC grinding wheels can be readily shaped for use in precision cylindrical form grinding, has been exploited for cost-effective production of PSZ components in automotive applications [1]. Several important effects were noted in studies on SiC-grinding of MgO-PSZ [2]. X-ray diffraction showed that the monoclinic phase was not present in the grinding chips. In contrast, the ground surfaces contained excess, relative to unground surfaces, of the monoclinic phase. This implies that the local hot-spot (flash) temperatures generated in PSZ grinding chips must be at least 1500 K, while the overall surface remains at a lower temperature. It has also been suggested that very high hot-spot temperatures would soften the ceramic and thereby contribute to the excellent grinding performance observed with SiC wheels. Motivated by these studies, the research reported here was undertaken to measure the grinding temperatures when using SiC wheels for grinding a 9 mol% MgO-PZS Coors ceramic.