Analysis on Initiation and Propagation Behavior of In-situ Tensile Crack in A356 Alloy
The fracture mechanism of A356 alloys as-cast was investigated. The crack initiation and propagation process were examined by in-situ tensile test using scanning electron microscope. The results show that crack initiates first in the lamellar eutectic area and block eutectic silicon phases. Crack propagates along the matrix/ silicon particle interface. The eutectic Si particles can block the propagation of crack. The crack paths deflect to the weaker area when encountering with Si particles.