摘要
The microstructure and mechanical properties of cast Mg-9Al-2Sn-xMn(x=0,0.1,0.3 wt.%)alloys in as-cast,solution treated and aged conditions are investigated.The results reveal that Mn addition into Mg-9Al-2Sn alloy leads to the formation of Al8(Mn,Fe)5 phases,the grain refinement and the increase of discontinuous Mg17Al12 precipitates along the grain boundaries.0.1 wt.%Mn addition has an obvious effect on accelerating the aging behavior of Mg-9Al-2Sn alloy at the early aging period up to 8 h,while 0.3 wt.%Mn addition alloy has an comparable aging behavior with the Mn-free alloy.Mn addition has less influence on the fracture behavior of Mg-9Al-2Sn alloy,while the fracture pattern is mainly determined by the thermal conditions.Mg-9Al-2Sn-0.1Mn alloy has the best combination of strength and elongation when aged at 200℃ for 8 h and the yield strength,ultimate tensile strength and elongation are 154 MPa,292MPa and 5%,respectively.
基金
This research work is collaborated by General Motors Global Research and Development(GM R&D),Warren,MI,USA,and Shanghai Jiao Tong University(SJTU),Shanghai,China.Dr P.Fu would like to acknowledge the support of a Specialized Research Fund for the Doctoral Program of Higher Education(20110073120008)
a project from Shanghai Science and Technology Committee(12DZ0501700).
