Effect of Al addition on formation and mechanical properties of Mg-Cu-Gd bulk metallic glass

The effect of partial substitution of Al for Cu on the glass forming ability(GFA) and mechanical properties of Mg65Cu25-xAlxGd10 (x=0, 1, 3 and 5, molar fraction, %) alloys were studied by X-ray diffractometry(XRD), differential scanning calorimetry(DSC) and uniaxial compression test. The result reveals that GFA of the alloys changes slightly with increasing x from 0 to 3, and then abruptly decreases with x increasing up to 5. The plasticity can be greatly improved with appropriate substitution of Cu by Al (3%, molar fraction) in Mg65Cu25Gd10 bulk metallic glass, and the resultant fracture strength, total strain to failure, and plastic strain are 898 MPa, 2.19% and 0.2%, respectively.