Mechanical behavior analysis on SiC/Al composites via in-situ neutron diffraction combined with finite element methods

Abstract

In this study, in-situ neutron diffraction and finite element (FE) analysis were employed to analyze the mechanical behavior of SiC/Al composites with 9 (M9) and 25 (M25) vol% SiC during tensile tests. The analysis of stress concentration factors in SiC/Al composites during the tensile process revealed that load-redistribution between the matrix and the reinforcement was accompanied by local and overall plastic deformation. The strength analysis shows that the load transfer and the dislocation strengthening were the main reasons for the strength increase. The dislocation strengthening and load transfer strengthening of M25 were 4 and 3 times higher than that of M9, respectively. In addition, during the tensile process, the load-redistribution occurred simultaneously with micro-yielding. The comparison between the external loading-macro elastic strain and stress-strain curves could reflect the micro-yielding beginning. It was found that the micro-yielding of M25 was more obvious, because more stress concentration around reinforcement and a large number of movable thermal mismatch dislocations were induced at high content reinforcement.