Optimization of Coating Layers in the Design of Ceramic Fiber Reinforced Metal Matrix Composites

Abstract

The potential of using coating layers to reduce thermal stresses in the matrix of composites with a mismatch in coefficients of thermal expansion (CTE) of fiber and matrix is investigated. Two thermoelastic solutions based on a 3-cylinder model are developed and a comprehensive sensitivity study is conducted. It is shown that the performance of the layer can be defined by the product of its CTE and thickness, and that a compensating layer with a sufficiently high CTE can reduce the thermal stresses in the matrix significantly. A practical procedure offering a window of coating layer candidates is proposed. Easy-to-use contours of matrix stress reduction factors are produced.