Effects of Cu and Mn on mechanical properties and damping capacity of Mg-Cu-Mn alloy

The effects of Cu and Mn additions on mechanical properties and damping capacity of Mg-Cu-Mn alloy were investigated. The tensile properties and damping capacity at room temperature of as-cast Mg-Cu-Mn alloy were tested. The microstructure was studied using optical microscope, X-ray diffraction and scanning electron microscope. The Hall-Petch relation and Granato-Lücke model were used to explain the influences of Cu and Mn additions on the tensile properties and damping capacity of Mg-Cu-Mn alloy. The results show that Cu and Mn additions remarkably reduce the grain size of Mg-Cu-Mn alloy, but have little influence on phase composition and solute atoms concentration, the tensile properties increase obviously and the internal friction of Mg-Cu-Mn alloy decreases with grain refining.