Microstructures and mechanical properties of AZ91D/0Cr19Ni9 bimetal composite prepared by liquid-solid compound casting  

液-固复合铸造AZ91D/0Cr19Ni9双金属复合材料的显微组织和力学性能（英文）

作　　者：Jian-hua ZHAO Wen-qun ZHAO Shen QU Yan-qing ZHANG 赵建华;赵文群;屈伸;张彦青(重庆大学机械传动国家重点实验室,重庆400044;重庆大学材料科学与工程学院,重庆400044)

机构地区：[1]State Key Laboratory of Mechanical Transmission, Chongqing University, Chongqing 400044, China [2]College of Materials Science and Engineering, Chongqing University, Chongqing 400044, China

出　　处：《Transactions of Nonferrous Metals Society of China》2019年第1期51-58,共8页中国有色金属学报（英文版）

基　　金：Project(cstc2015yykfC0001)supported by the National Engineering Research Centre for Magnesium Alloys,China;Project supported by State Key Laboratory of Mechanical Transmission of Chongqing University,China

摘　　要：The liquid-solid compound casting technology was used to produce the AZ91D/0Cr19Ni9 bimetal composite without and with hot dipping aluminium, respectively. The influences of Al coating on microstructures and mechanical properties of AZ91D/0Cr19Ni9 interface were investigated. The results showed that the mechanical bonding was obtained between AZ91D and bare steel 0Cr19Ni9 where a gap existed at the interface; the metallurgical bonding was formed between AZ91D and Al-coated 0Cr19Ni9, which could be divided into two different intermetallic layers: layer Ⅰ was mainly composed of α-Mg+β-Mg17Al12 eutectic structure and a small amount of MgAl2O4, and layer Ⅱ mainly comprised of Fe2Al5 intermetallic compound. Furthermore, the hardness value of interface was obviously higher than that of AZ91D matrix, and the average hardness values of layers Ⅰ and Ⅱ were HV 158 and HV 493, respectively. The shear strength of AZ91D/Al-coated 0Cr19Ni9 interface was higher than that of AZ91D/bare 0Cr19Ni9 interface, which confirmed that Al coating could improve the adhesive strength between AZ91D and 0Cr19Ni9 during liquid-solid compound casting process.采用液-固复合铸造技术制备未经表面处理和经热浸镀铝表面处理的AZ91D/0Cr19Ni9双金属复合材料,研究铝涂层对AZ91D/0Cr19Ni9界面显微组织和力学性能的影响。结果表明:镁合金和裸钢0Cr19Ni9之间为机械结合,结合界面处存在一缝隙;而镁合金AZ91D和镀铝钢0Cr19Ni9之间形成冶金结合,且镁合金AZ91D/镀铝钢0Cr19Ni9界面可以分为两个不同的金属间化合物层:层Ⅰ主要由α-Mg+β-Mg_(17)Al_(12)共晶组织和少量的MgAl_2O_4相组成,层Ⅱ主要由Fe_2Al_5金属间化合物组成。此外,结合界面的硬度明显高于镁合金基体AZ91D的硬度,层Ⅰ和层Ⅱ的平均硬度分别为HV158和HV493。镁合金AZ91D/镀铝钢0Cr19Ni9界面的剪切强度高于镁合金AZ91D/裸钢0Cr19Ni9界面的剪切强度,这证明在液-固复合铸造过程中铝涂层能提高镁合金AZ91D和钢0Cr19Ni9之间的结合强度。

关 键 词：AZ91D 0CR19NI9 liquid-solid compound casting interface bonding shear strength 

分 类 号：TB331[一般工业技术—材料科学与工程] TG24[金属学及工艺—铸造]