Er添加及Mg/Si比对Al-Mg-Si合金组织及性能的影响  

Effect of Er addition and Mg/Si ratio on microstructure and properties of Al-Mg-Si alloy

作　　者：董建华 王瑞红[1] DONG Jian-hua;WANG Rui-hong(School of Materials Science and Engineering,Xi’an University of Technology,Xi’an 710048,China)

机构地区：[1]西安理工大学材料科学与工程学院,陕西西安710048

出　　处：《材料热处理学报》2024年第12期58-65,共8页Transactions of Materials and Heat Treatment

基　　金：国家自然科学基金(52071260)。

摘　　要：采用光学显微镜(OM)、扫描电镜(SEM)、透射电镜(TEM)、显微硬度计、电导率测试仪和拉伸试验等研究了不同含量Er的添加及Mg/Si比对Al-Mg-Si合金微观组织和性能的影响。结果表明:当Mg/Si为0.8及Er的添加量为0.3 mass%时,Al-Mg-Si合金峰值时效后β″相尺寸更小、数密度更大,人工时效强化效果得到提升,显微硬度提高了9%,电导率提高了2%IACS;适量Er(0.3 mass%)的添加诱导形成富含Al、Si、Er元素的第二相,有利于合金的强度和电导率提升;当Mg/Si比为0.4时,合金中由于Si含量的增加,可以析出更多的β″相,但其尺寸略有长大,有更好的时效强化效果,固溶时效后合金的峰值硬度为118 HV0.2,但由于析出相数密度的增大,导致析出相的平均间距变小,对合金电导率不利,由于Si含量的增多,Si与Er相互作用形成更多的富含Al、Si、Er元素的第二相,粗大的第二相不利于合金的塑性。Effect of different amounts of Er addition and Mg/Si ratio on microstructure and properties of Al-Mg-Si alloys was studied by means of optical microscope(OM),scanning electron microscopy(SEM),transmission electron microscopy(TEM),microhardness tester,conductivity tester and tensile test.The results show that when Mg/Si is 0.8 and the amount of Er added is 0.3 mass%,the size of theβ″phase in the Al-Mg-Si alloys is smaller and the number density is higher,the artificial aging strengthening effect is improved,the microhardness increases by 9%,and the increment of the conductivity is 2%IACS.The addition of an appropriate amount of Er(0.3 mass%)induces the formation of second phase rich in Al,Si and Er elements,which is beneficial for improving the strength and conductivity of the alloy.When the Mg/Si ratio is 0.4,moreβ″phases can precipitate in the alloy due to the increase of Si content,but their size slightly increases,resulting in better aging strengthening effect,and after solution and aging treatment,the peak hardness of the alloy is 118 HV0.2.However,due to the increase of the number density of precipitated phases,the average spacing between precipitated phases becomes smaller,which is not conducive to the electrical conductivity of the alloy.Due to the increase of Si content,Si interacts with Er to form more second phases rich in Al,Si and Er elements,and coarse second phases are not conducive to the plasticity of the alloy.

关 键 词：AL-MG-SI合金 稀土Er Mg/Si比 力学性能 

分 类 号：TG146.2[一般工业技术—材料科学与工程]