ABSTRACT
The effect of different Ca contents on the microstructure and mechanical properties of Mg-5Al-1Bi-0.3Mn (AMB501) magnesium alloys was investigated by conventional melting and casting technique using different Ca contents (1.0, 2.0, and 3.0 wt %). Increasing the Ca content resulted in higher hardness and yield strength, but decreased elongation. The improved tensile properties of the AM50-1Bi-xCa alloys were due to the changes in AMB501 alloy microstructure when the Ca content increased, as demonstrated by scanning electron microscope, energy dispersive spectrum, and X-ray diffractometer. The alloy microstructure indicated that the amount of ß-Mg17 Al12 phase on grain boundaries decreased and the morphology of ß-Mg17 Al12 phase on grain boundaries changed from quasicontinuous-net shape to dispersed particles. The Mg17 Al12 phase disappeared and a new secondary phase Al2 Ca appeared after a 3.0 wt % Ca addition.
