Published online by Cambridge University Press: 20 October 2014
Different parts of a casting may receive different microstructures during cooling particularly for the large scale casting, which can affect the fatigue behavior. In the present study, in consideration of the safety and reliability, the microstructures, tensile properties, and high cycle fatigue behaviors of different regions in a low-pressure sand-cast Mg–10Gd–3Y–0.5Zr (GW103K) magnesium alloy component with large scale and complicated structure were investigated. The results showed that the tensile properties particularly ultimate tensile strength (UTS) and elongation (EL) varied with regions and the fatigue strength varied in a range from 100 to 115 MPa. In addition, crack initiation, crack propagation, and fracture behavior of the studied alloys after tensile test and high cycle fatigue test were also investigated systematically.