The factors affecting the performance and fracture mechanism of low-pressure casting A356.2 aluminum alloy wheel spokes were investigated by analysis of secondary dendrite arm spacing

fracture surface and micro-area composition based on testing mechanical properties and observing microstructure of the samples from different shape aluminum alloy wheel spokes. The results show that different type pokes exhibit high strength and low plasticity

in which the yield strength shows relatively steady because it is mainly controlled by the matrix phase state

and the elongation controlled by the internal defects of castings indicates evident change

and the tensile strength exhibits the same trend as the elongation. The impurities and holes are distributed in the tensile fracture surface

and by spectrum analysis

there exists C and O elements at the fracture surface resulted from the dregs and oxide films led by casting process

meanwhile

Fe elements is also relatively aggregated in the spokes. The quasi-cleavage plane and dimple morphology are observed in fracture surface

which shows that fracture mechanism is characterized by the ductile-brittle mixed fracture mode

and the crack is propagated along the eutectic region among dendrite cell.