Er和Zn对压铸Al-9Si-0.6Fe-0.2-Mn-0.2Mg合金组织和性能影响

Effects of Er and Zn on Microstructure and Properties of As-cast Al-9Si-0.6Fe-0.2Mn-0.2Mg Alloys

使用普通卧式压铸机制备了Al-9Si-0.6Fe-0.2Mn-0.2Mg-X(X=0.2Er、0.4Er、0.6Er、0.4Er+1.5Zn)合金的压铸拉伸试样,并采用金相显微镜、扫描电镜、电子探针和电子万能材料试验机等研究了其铸态显微组织和力学性能。结果表明,在Al-9Si-0.6Fe-0.2Mn-0.2Mg合金中单一添加0.4%的Er时,合金组织中的α-Al和共晶Si细化变质效果相对较好,其抗拉强度为228.1 MPa;复合添加0.4%的Er+1.5%Zn时,合金组织中的共晶Si相和α-Al相变得更加细小、圆整,提升了合金的综合力学性能,其抗拉强度、伸长率和硬度(HV)分别达到了278.2 MPa、6.3%和91.9。

Al-9Si-0.6Fe-0.2Mn-0.2Mg-X(X=0.2Er,0.4Er,0.6Er,0.4Er+1.5Zn,%)alloys were prepared by horizontal die casting machine.The microstructure and mechanical properties of die casting and tensile specimens were investigated by means of metallographic microscope,scanning electron microscope,electron probe and electronic universal material tester.The results indicate that with single addition of 0.4%Er,the modification effect ofα-Al and eutectic Si is desirable,where the tensile strength is 228.1 MPa.With compound addition of 0.4%Er+1.5%Zn,the eutectic Si andα-Al phase become finer and rounder,improving the comprehensive mechanical properties of the alloy,where the tensile strength,elongation and hardness reach 278.2 MPa,6.3%and 91.9 HV,respectively.