Failure probability analysis for a RBSN cylinder with a SiC coating subjected to a radial heat flux

Abstract

A failure probability assessment procedure, based on a development of the Weibull probability distribution function, is described. The procedure is applied in the case of a cylindrical reaction bonded silicon nitride (RBSN) shell with a thin surface layer of silicon carbide (SiC) subjected to a constant (steady-state) heat flux. The dependence of the failure probability on the Weibull modulus of the material, and the thickness and thermal conductivity of the coating is systematically studied and the results are critically discussed. The work provides a basis for a sensitivity analysis and design appraisal of compound cylinders consisting of two brittle materials and subjected to thermal stresses.