Inhomogeneity of internal stresses and X-ray elastic constants of ceramic materials

Abstract

Experimental determination and theoretical calculation of the so-called X-ray elastic constants, which describe the relation between the lattice strain and the stress, were carried out to test the validity of traditional methods of calculation of X-ray elastic constants for heterogeneous ceramic materials. For this investigation materials such as α-Al 2O 3, α-Al 2O 3/ZrO 2, and TiC/ α-Al 2O 3TiB 2 were used. It was found that the values of elastic constants, calculated for multiphase systems, may produce significant errors when used to determine the internalstress. The discrepancy between calculated and experimental values may be utilized as a diagnostic test of inhomogeneity of the material being investigated.