杂质Fe和Si对Al-Cu-Mn-Mg合金显微组织及力学性能的影响  

Effect of impurities Fe and Si on microstructure and mechanicalproperties of Al-Cu-Mn-Mg alloy

作　　者：余文涛 孟祥炜 张晗 郝启堂[4] 薛彦庆 YU Wen-tao;MENG Xiang-wei;ZHANG Han;HAO Qi-tang;XUE Yan-qing(Shaanxi Key Laboratory of Surface Engineering and Remanufacturing,Xi’an University,Xi’an 710065,China;Xi’an Key Laboratory on Intelligent Additive Manufacturing Technologies,Xi’an University,Xi’an 710065,China;Capital Aerospace Machinery Corporation Limited,Beijing 100076,China;State Key Laboratory of Solidification Processing,Northwestern Polytechnical University,Xi’an 710072,China)

机构地区：[1]西安文理学院陕西省表面工程与再制造重点实验室,陕西西安710065 [2]西安文理学院西安市智能增材制造重点实验室,陕西西安710065 [3]首都航天机械有限公司,北京100076 [4]西北工业大学国家凝固重点实验室,陕西西安710072

出　　处：《材料热处理学报》2023年第12期35-43,共9页Transactions of Materials and Heat Treatment

基　　金：2021年陕西省重点研发计划项目(2021ZDLGY14-07);陕西省自然科学基础研究计划(2023-JC-YB-409)。

摘　　要：采用光学显微镜(OM)、扫描电镜(SEM)和透射电镜(TEM)等研究了杂质Fe和Si对Al-Cu-Mn-Mg合金显微组织及力学性能的影响。结果表明:当合金含有0.20 mass%的杂质Fe时,凝固过程中形成的富Fe相为Al_(7)Cu_(2)(FeMn),与不含杂质Fe时相比,合金的力学性能略有下降,但仍具有良好的塑性。当合金含有0.20 mass%的Fe和0.20 mass%的Si时,热处理后合金中存在两种富Fe相,Al_(7)Cu_(2)(FeMn)和Al_(15)(FeMn)_(3)(SiCu)_(2)相,但Al_(7)Cu_(2)(FeMn)相居多。此外,含有杂质Fe和Si的合金凝固终了时在晶界处形成低熔点共晶组织(Al+Al_(2)Cu+Mg_(2)Si),导致合金在热处理过程中发生过烧现象。与仅含杂质Fe元素的合金相比,同时含有Fe和Si时合金的抗拉强度变化不大,但屈服强度增加了51.6 MPa,伸长率由15.4%大幅下降至6.0%。Effect of impurities Fe and Si on microstructure and mechanical properties of Al-Cu-Mn-Mg alloy was studied by means of optical microscope(OM),scanning electron microscopy(SEM)and transmission electron microscopy(TEM).The results show that when the alloy contains 0.20 mass%impurity Fe,the Fe-rich phase formed during solidification is Al_(7)Cu_(2)(FeMn).Compared with the alloy without impurity Fe,the mechanical properties of the alloy slightly decrease,but it still has good plasticity.When the alloy contains 0.20 mass%Fe and 0.20 mass%Si,there are two Fe-rich phases in the alloy after heat treatment,which are Al_(7)Cu_(2)(FeMn)and Al_(15)(FeMn)_(3)(SiCu)_(2) phases,but the Al_(7)Cu_(2)(FeMn)phase is the majority.In addition,the alloy containing impurities Fe and Si form a low melting point eutectic structure(Al+Al_(2)Cu+Mg_(2) Si)at the grain boundaries at the final stage of solidification,leading to the occurrence of over-burning during the heat treatment of the alloy.Compared with the alloy containing only impurity Fe,the tensile strength of the alloy with both Fe and Si does not change much,but the yield strength increases by 51.6 MPa and the elongation decreases significantly from 15.4%to 6.0%.

关 键 词：Al-Cu-Mn-Mg合金 富Fe相 过烧 共晶相 

分 类 号：TG146.2[一般工业技术—材料科学与工程]