Holographic investigation into the mechanical behaviour of engineering ceramics

Abstract The complex loading conditions to which a structural component is customarily subjected require a knowledge of the material responses to combined stresses, while almost all the data available for ceramic materials are obtained from uniaxial tests. It is necessary, therefore, to study the behaviour of engineering ceramics using specimens of proper shapes subjected to biaxial stresses and testing methods that enable high sensitivity monitoring and real time analysis of the surface strains. In this respect, an optical technique such as conjugate wave holographic interferometry gives satisfactory results. Characterisation tests are carried out on diametrically loaded discs in order to evaluate Young's modulus and Poisson's ratio of some classes of ceramic materials.