<span>AlSi合金中间层对铝/镁扩散连接界面组织性能的影响<br /></span> <br />-中国材料进展

文章信息/Info

Title:: Effect of AlSi Alloy Interlayer on Microstructure and Mechanical Properties of Diffusion-Bonded Mg/Al Joints

作者:: 刘宁1; 刘灿春1; 付莹2; 殷福星1; 梁春永1; （1. 河北工业大学材料科学与工程学院，天津 300130）
（2. 渤海大学工学院，辽宁锦州 121013）

Author(s):: LIU Ning1; LIU Canchun1; FU Ying2; YIN Fuxing1; LIANG Chunyong1; (1. School of Materials Science and Engineering, Hebei University of Technology, Tianjin 300130, China)
(2. Engineering Department, Bohai University, Jinzhou 121013, China)

Keywords:: aluminum/magnesium composites; interlayer; interface; diffusion; bonding strength

摘要:: 以Al-10Si合金粉末和纯Al粉混合（质量比为1∶1）粉末为中间层，在450 ℃下保温1 h，对工业纯铝和工业纯镁进行了扩散连接。采用扫描电子显微镜(SEM)、电子探针(EPMA)分析了界面区域的微观组织和元素分布。结果表明，在450 ℃下保温1 h，混合粉末与铝、镁两侧基体间发生元素扩散，形成梯度结构的反应层，反应层从铝侧向镁侧依次为Al3Mg2层（Ⅰ）、Al12Mg17层（Ⅱ）、富硅相层（Ⅲ）和Al12Mg17 + δMg（Ⅳ）共晶层。反应层总厚度约为520 μm，且富硅相层的厚度大于其它3层。硬度测试结果显示，Al和Mg两侧基体的平均硬度（HV）分别为242和478 MPa，靠近Al侧的Al3Mg2化合物层硬度最高，硬度值为2520 MPa；Al12Mg17 + δMg共晶区域的平均硬度为2100 MPa，而富硅相层区域的平均硬度为1980 MPa。拉伸剪切试验结果显示，增加AlSi合金中间层后，Al/Mg异种金属扩散连接界面结合强度达到23 MPa；拉伸剪切断口XRD分析表明，断裂位置位于硬度值最高的Al3Mg2化合物层，拉伸断口呈现典型的脆性断裂特征。

Abstract:: Al-10Si alloy powder and pure Al powder (with a ratio of 1∶1) were mixed as the intermediate layer, and the diffusionbonded Mg/Al joints with the interlayer have been investigated. Scanning electron microscopy (SEM) and electron probe (EPMA) were used to analyze the microstructure and element distribution in the interface region. The results show that elemental diffusion occurs between the mixed powder layer and the bases, forming a gradient structure reaction layer. Al3Mg2, Al12Mg17, Sirich phase and Al12Mg17 + Mg eutectic layers are observed in the interface from Al side to Mg side. The thickness of the Sirich phase layer is greater than that of the other three layers. The hardness test results show that the average hardness value of aluminum and magnesium bases are 242 and 478 MPa, respectively. The Al3Mg2 intermetallic compound layer near the Al side has the highest hardness, which reaches 2520 MPa. Meanwhile, the average hardness value of the Al12Mg17 + Mg eutectic and the Sirich phase layers are 2100 and 1980 MPa, respectively. Tensileshear test results show that the bonding strength of Al/Mg joint with the interlayer is 23 MPa. The XRD analysis shows that the fracture site is located in the Al3Mg2 layer. The fractures exhibit typical brittle fracture characteristics.