Influence of Thermal Residual Stresses on the Behaviour of Metal Matrix Composite Materials

Abstract

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In this article, numerical simulations are used to study the bonding of ceramic–metal interfaces as well as ceramic-reinforced metal matrix composites (MMCs). For the design of the geometrical model of the MMC, the reinforcement is considered to be discontinuous (MMCD) and it consists of particles in which their distribution is homogeneous within the composite material. As a consequence of the existence of residual stresses in the material, there will be higher compressive stresses in the reinforcement and higher diferences of stress values between the matrix and the reinforcement than those found without them. The novelty of this research lies in the fact that through the knowledge of the stress states at a given distance from the interface, the manufacturing processes of the MMCs could actually be improved. After the simulations, it is observed that the reinforcement is compressed due to the diference between the two thermal expansion coefcients of the constituent materials. The matrix is also compressed in the incident zone longitudinal to the reinforcement and in the zone surrounding the fbre in the radial direction. However, the matrix is tensioned in the longitudinal direction parallel to the reinforcement and in the transverse direction around the particle.