Calculation of adhesion strength at the interface of a coated particle embedded within matrix under multiaxial load

Analytical and finite element solutions of the stress fields around a parti cle under multiaxial thermomechanical load are derived as functions of the properties of the particle, the matrix and an interphase. The motivation fo r these calculations is to answer the question of how to load a sample cont aining a particle to measure the adhesion strength at the interfaces. The c alculations provide the stress field and show that an interphase with a You ng's modulus lower than that of the matrix reduces stress concentration in the neighbourhood of the particle. The superposition of loads in different directions results in the creation of a more or less uniform distribution o f tensile stresses (hydrostatic tension) around the particle, a stress situ ation that allows the determination of adhesion strength. The ratio of the applied stresses in different directions determines the extension of the ar ea which is under high tensile loads. This provides the basis to develop a test technique for the examination of statistical effects which in addition to the bonding quality may influence adhesion strength at interfaces. (C) 2000 Elsevier Science B.V. All rights reserved.