The adhering sand behavior of high strength A357 aluminum alloy transition ring castings during the pouring and solidification process was analyzed.Through the metallographic microstructure observation

micro-hardness measurements

SEM（scanning electron microscope） and EDS（energy dispersive spectrometer） and mechanical properties testing

serious adhering sand defects area were analyzed and identified.The results show that interface chemical reaction nearby the sand burning area can not be observed

and the internal casting defects in the cavity belong to mechanical adhering sand by the X-ray diffraction

which is attributed to the capillary permeability and gas phase penetration effect as a result of high temperature melting aluminum strongly eroding the surface coating of resin sand mould.With adding resistant high temperature oxide into the coating and increasing the coating’s thickness

the severity of mechanical adhering sand among the interface area is relieved

improving greatly the mechanical properties of the A357 aluminum alloy transition ring castings.