NONDESTRUCTIVE TESTING OF HIGH TEMPERATURE NON-METALLIC MATERIALS.

A review of the application of current techniques of nondestructive testing to high temperature non-metallic materials such as ceramics, refractories and glasses is presented. Of particular importance is the technique of acoustic emission, which is shown to be suitable in the prediction of failure time in materials as well as in the evaluation of crack propagation rates. Failure of these materials is analyzed in terms of linear elastic fracture mechanics and the correlation between acoustic emission and fracture mechanics is reviewed.