Characterization of Binary Mg-Mn Alloy Synthesized through Mechanical Alloying: Effects of Milling Speed

Abstract

In this work, the effect of the milling speed on the properties of biodegradable Mg-1Mn alloy prepared by mechanical alloying was investigated. The magnesium-based alloy was prepared in solid state route using a high energy planetary mill. A mixture of pure magnesium and manganese powder was mechanically alloyed for 5 hours in argon atmosphere. Milling process was performed at various rotational speeds in order to investigate milling speed effect (i.e., 100, 200, 300 and 400 rpm) on phase formation and bulk properties. The as-milled powder was uniaxially compacted by cold pressing under 400 MPa at room temperature and sintered in argon atmosphere at 500 °C for an hour. X-ray diffraction analysis indicated that a single α-Mg phase was formed in magnesium matrix after sintering process. An increase in milling speed up to 300 rpm resulted in an increase in density and hardness of the binary alloy. The changes of bulk properties of the Mg-Mn alloys were correlated to the formation of solid solution phase and a reduction of porosity which led to an increasing in densification.