Abstract
During sintering of metal/ceramic functionally graded materials, cracks often appear on the surface of the top ceramic layer due to the internal stress produced by mismatch shrinkage and warpage in multilayers. The ways to reduce the internal stress in the graded powder compacts are examined by using the analysis of sintering process. Thinning the top layer is found to be effective in reducing the tensile stress on the surface when the sintering properties of some layers are modified appropriately. The suppression of the surface cracking in the improved graded powder compacts is verified in experiment.
