Effect of Si addition and applied pressure on microstructure and tensile properties of as-cast Al-5.0Cu-0.6Mn-1.2Fe alloys  

Si添加和压力对铸造Al-5.0Cu-0.6Mn-1.2Fe合金组织和力学性能的影响（英文）

作　　者：Wei-wen ZHANG Yu-liang ZHAO Da-tong ZHANG Zong-qiang LUO Chao YANG Yuan-yuan LI 张卫文;赵愈亮;张大童;罗宗强;杨超;李元元(华南理工大学国家金属材料近净成形工程技术研究中心,广州510641)

机构地区：National Engineering Research Center of Near-net-shape Forming for Metallic Materials,South China University of Technology,Gnangzhou 510641,China

出　　处：《Transactions of Nonferrous Metals Society of China》2018年第6期1061-1072,共12页中国有色金属学报（英文版）

基　　金：Project(51374110)supported by the National Natural Science Foundation of China;Project(2015B090926004)supported by Science and Technology Program of Guangdong Province,China;Project(2015A030312003)supported by the Natural Science Foundation of Guangdong Province,China

摘　　要：The effects of Si addition and applied pressure on the microstructure and tensile properties of as-cast Al-5.0 Cu-0.6 Mn-1.2 Fe alloys were studied. The results show that Si addition promotes the formation of Chinese script α-Fe, and suppresses the precipitation of Al_3（Fe Mn） and Al_6（Fe Mn）. For the alloys produced without pressure, Si addition increases the volume fraction of porosity, resulting in remarkable decrease in ultimate tensile strength（UTS） and yield strength（YS）. For the alloys produced with 75 MPa pressure, Si addition improves UTS and YS owing to the formation of high number density of Al_2 Cu（θ） phases. The tensile properties of alloys increase with increasing applied pressure at the same Si content level, which is attributed to elimination of porosity, grain refinement strengthening and solid-solution strengthening. The alloy with 1.1% Si addition and 75 MPa pressure shows the best tensile properties, where the UTS, YS and elongation are 237 MPa, 140 MPa and 9.8%, respectively.研究Si添加和压力对铸造Al-5.0Cu-0.6Mn-1.2Fe合金显微组织和力学性能的影响。结果表明,添加Si可促进α-Fe的形成,并抑制Al3(FeMn)和Al6(FeMn)的形成。对于重力铸造的合金,添加Si会增加孔洞的体积分数,导致合金的抗拉强度(UTS)和屈服强度(YS)显著降低。对于在75 MPa压力下制备的合金,Si添加促进高密度Al2Cu(θ)相的形成,从而使抗拉强度和屈服强度增加。在相同Si含量的合金中,力学性能随施加压力的增加而增加,这是由于孔洞减少、晶粒细化强化和固溶强化所致。合金最好的力学性能出现在压力为75 MPa和Si含量为1.1%时,其UTS、YS和伸长率分别为237 MPa、140 MPa和9.8%。

关 键 词：Al-Cu alloys Si addition SOLIDIFICATION tensile properties MICROSTRUCTURE 

分 类 号：TG146.21[一般工业技术—材料科学与工程] TG249.2[金属学及工艺—金属材料]