Mesoscale numerical analysis of deformation and fracture in coated materials

摘要

Presented is the numerical analysis of deformation and fracture in materials with wear resistantiron boride coating and a composite coating providing oxidation protection.A dynamic boundaryvalueproblem in a plane strain formulation is solved numerically by the finite-difference method.The coating-substrate interface geometry corresponds to the configuration found experimentallyand is accounted for explicitly in the calculation.To simulate the mechanical response of a substrateand a coating use was made of the relaxation constitutive equation based on microscopic dislocationmechanisms and a fracture model taking into account crack initiation and growth in the regions ofbulk tension.A series of numerical experiments was conducted at different scales and for varyingstrain rate of tension/compression.The following conclusions can be drawn.( ).