Effect of rolling reduction and annealing process on microstructure and corrosion behavior of LZ91 alloy sheet  

轧制变形量及轧后退火对LZ91镁合金板材显微组织和耐腐蚀性能的影响

作　　者：Li-na MA Yan YANG Gang ZHOU Feng-juan REN Hong-ju DENG Guo-bing WEI Xiao-dong Peng 马丽娜;杨艳;周港;任凤娟;邓洪举;魏国兵;彭晓东(重庆大学材料科学与工程学院轻合金材料国际合作联合实验室,重庆400044;重庆大学机械传动国家实验室,重庆400044;重庆大学国家镁合金材料工程技术研究中心,重庆400044)

机构地区：[1]International Joint Laboratory for Light Alloys,College of Materials Science and Engineering,Chongqing University,Chongqing 400044,China [2]State Key Laboratory of Mechanical Transmissions,Chongqing University,Chongqing 400044,China [3]National Engineering Research Center for Magnesium Alloys,Chongqing University,Chongqing 400044,China

出　　处：《Transactions of Nonferrous Metals Society of China》2020年第7期1816-1825,共10页中国有色金属学报（英文版）

基　　金：Projects(2016YFB0700403;2016YFB0301100)supported by the National Key Research and Development Program of China;Project(cstc2019jcyj-msxmX0306)supported by the Chongqing Research Program of Basic Research and Frontier Technology,China;Projects(2018CDGFCL0005;2018CDJDCL0019)supported by the Fundamental Research Funds for the Central Universities,China;Project(B16007)supported by the 111 Program of Ministry of Education and the State Administration of Foreign Experts Affairs of China。

摘　　要：The effect of rolling reduction and annealing process on the microstructure and corrosion behavior of Mg-9Li-1Zn(LZ91) alloy was investigated. The test alloy sheets were cold rolled with the reduction of 50% and 75%, respectively, and then were annealed at 200 ℃ for 1 h. The microstructure of test alloys was observed by OM and SEM while the phase composition was determined by XRD. The corrosion property was evaluated by electrochemical measurements and immersion tests. The results show that LZ91 alloy sheet consists of α-Mg, β-Li and precipitated Mg-Li-Zn compounds(MgLi2Zn and MgLiZn phases). Dynamic recrystallization grains appear in β-Li phase during annealing process, leading to grain refinement. The results indicate that the increasing rolling reduction and performing the annealing process can enhance the corrosion resistance of LZ91 alloy. The 75% cold-rolled and annealed LZ91 alloy shows the best corrosion resistance.研究轧制变形量和轧后退火工艺对Mg-9Li-1Zn(LZ91)合金显微组织和耐腐蚀性能的影响。采用冷轧变形工艺制备轧制压下量分别为50%和75%的LZ91镁合金板材,然后在200℃下退火1 h。采用光学显微镜和扫描电子显微镜观察合金的显微组织,用X射线衍射仪测定合金中的相组成。结果表明,LZ91镁合金由α-Mg、β-Li和Mg-Li-Zn三元化合物(MgLi2Zn和MgLiZn相)组成。退火过程中β-Li相发生动态再结晶,合金晶粒细化。腐蚀试验表明:轧制变形和轧后退火能显著改善LZ91合金的耐腐蚀性能,75%冷轧退火LZ91镁合金具有最好的耐蚀性。

关 键 词：LZ91 alloy cold rolling ANNEALING MICROSTRUCTURE corrosion resistance 

分 类 号：TG146.22[一般工业技术—材料科学与工程] TG339[金属学及工艺—金属材料] TG156.2[金属学及工艺—金属学]