Abstract
Residual stress and bent deformation induced by diamond grinding of thin plate are studied on yttria-doped tetragonal zirconia polycrystals (Y-TZP). It is focussed to clarify the stresses and the deformations of the plates of various thicknesses by relating them with grinding conditions, and to confirm the role of phase transformation from tetragonal to monoclinic in Y-TZP on the stress and the deformation. The plates were ground with a machine of reciprocatory table type and their residual stress and bent deformation were measured with an X-ray stress analyzer and a profile tester, respectively. A model of partial expansion due to the phase transformation under the ground surface in Y-TZP was treated to calculate the stress and the deformation. The stresses and the deformations between measured and calculated were compared. The results are as follow. (1) The residual stress is compressive under the ground surface and becomes slightly smaller with decrease in the thickness of the plate. (2) The bent deformation shows parabola being convex on the ground surface and becomes very large with decrease in the thickness of the plate. (3) Change in work speed affects the residual stress and the bent deformation more largely than change in wheel depth of cut does. (4) The residual stresses induced by the phase transformation are distinguished from those by another causes.
