Effects of morphology of eutectic Si phase

size of α-Al dendrite in compound modified Al-Si series alloy on mechanical properties of the alloy were analyzed by fracture-metallographic method. It is found that refinement of α-Al dendrite and desirable morphology and distribution of eutectic Si in compound modification samples can restrain the crack propagation during tensile process and make the formation of small crack unit absorb more energy during crack process

which results in the increase of crack propagation paths in transgranular fracture

exhibiting the improvement of comprehensive mechanical properties of the Al alloy.