Modelling and experimental characterisation of phase strain evolution in 10 vol percent Al/SiCw composite during thermo mechanical loading

摘要

This paper addresses the experimental characterisation of the phase strain response to thermo mechanical loading using neutron diffraction, with the aim to evaluate numerical predictions of phase strain evolution. By the use of neutron diffraction we characterise the initial residual phase strains in the two phases of a 10vol percent Al/SiCw composite. When compared to numerical simulations by the Finite Element Method (FEM), it is apparent, that such predictions over estimates the thermal residual phase strains. FEM simulations of subsequent room temperature loading shows some discrepancies as compared to neutron diffraction experiments, though the phase strain evolution is qualitatively in agreement with the experimental evidence. It is evident that the cell-model idealsation of real composites does not accurately reflect the real state of internal stress development in the two constituent phases.