304钢/QAl9-4铝青铜复合界面的显微组织及性能  

Microstructure and properties of 304 steel/QAl9-4 aluminum bronze composite interface

作　　者：袁颖[1] Yuan Ying(High Institute of Technology, Xi＇an University of Technology, Xi＇an Shaanxi 710048, China)

机构地区：[1]西安理工大学高等技术学院

出　　处：《金属热处理》2018年第4期198-203,共6页Heat Treatment of Metals

基　　金：陕西省教育厅项目(KSJ004)

摘　　要：采用真空扩散焊接技术制备304不锈钢与QAl9-4铝青铜双金属复合材料，通过金相显微镜（OM）、扫描电镜（SEM）、透射电镜（TEM）、X射线衍射仪（XRD）分析了钢／铜复合界面的显微组织、相结构及化学成分，利用硬度测定仪及拉伸试验测试了界面处的力学性能。结果表明：在（1150±50）℃、4．0×10^-2Pa真空条件下，界面结合紧密，基体两侧的Fe、A1、Cu等合金原子发生互扩散，形成宽约140gm的过渡层，主要物相为MCrFe2、Al4Cu9、MNi3等，显微硬度最大值为420HV0．02。复合材料的抗拉强度是278MPa，拉伸断口在复合界面处，呈脆性断裂特征。钢／铜扩散焊接的机理是基体钢中Fe、cr等元素优先在铜表面铺展润湿，在界面处与其他合金原子（A1、Cu等）发生相互扩散形成过渡层，最终形成良好的冶金结合。QA19-4 aluminum bronze and 304 stainless steel bimetal composites were fabricated by vacuum diffusion welding process. Microstructure, phase structure and chemical composition were characterized by means of TEM, XRD, OM and SEM. Mechanical properties of interface were studied by means of tensile tests and hardness measurement. The results show that the interface of 304/QA19-4 composites is tightly bonded, and the Fe, A1 and Cu atoms on the two sides of the matrix inter-diffuse and form a transition layer with thickness of about 140 μm. The main phases are A1CrFe2, A14Cu9 and A1Ni3 , and the maximum hardness is 420 HV0.02 at the condition of （ 1150 ±50） ℃ with pressure of 4.0 ×10^-2 Pa. The tensile strength of the composite is 278 MPa, and the fracture is at the interface, which is typical of brittle fracture. The mechanism of steel/copper diffusion welding is that the Fe, Cr elements in the base steel first spread and wet on the copper surface, then at the interface form a transition layer with the other alloying atoms （A1, Cu, etc. ） and finally form a good metallurgical union layer,

关 键 词：QAl9-4铝青铜 304不锈钢 真空扩散焊 界面 组织 性能 

分 类 号：TG113[金属学及工艺—物理冶金]