A micro-macro correlation analysis for metal matrix composites undergoing multiaxial damage

This three dimensional elastoplastic finite element analysis focuses on the macroscopic response to microscopic damage development, and the correlation of extrinsic multiaxial parameters with the intrinsic damage criteria for metal matrix composites under multiaxial tensile loading. The interface debonding and particle fracture are incorporated in a body centred cubic (BCC) unit cell as a representative volume element of alumina particulate-reinforced 6061 aluminum alloy composites undergoing damage. It is found that the multiaxiality of applied stress increases the amplitude of the critical micro-stresses and changes their location. Plastic deformation in the matrix plays a dominant role in inducing damage, and this is clearly demonstrated through comparing the equibiaxial loading with a uniaxial one having the same equivalent stress value. Numerical results also show that an energy-based macroscopic damage parameter provides a unique relationship between the uniaxial and multiaxial loadings when correlating the micro-damage in the metal matrix composites. © 1997 Elsevier Science Ltd