注射成形增强半固态AZ91D镁合金的组织及性能  

Influence of Semi-Solid Injection Molding on Microstructure and Properties of AZ91D Mg Alloy

作　　者：宇文江涛 赵雄 董璐 牛立斌[3] 胡宇阳 YUWEN Jiangtao;ZHAO Xiong;DONG LU;NIU Libin;HU Yuyang(No.705 Research Institute of CSSC,Xi'an 710077,China;No.12 Research Institute of CSSC,Xingping 713102,China;College of Materials Science and Engineering,Xi'an University of Science and Technology,Xi'an 710054,China)

机构地区：[1]中国船舶集团有限公司第七O五研究所,陕西西安710077 [2]中国船舶集团有限公司第十二研究所,陕西兴平713102 [3]西安科技大学材料科学与工程学院,陕西西安710054

出　　处：《热加工工艺》2024年第6期122-127,共6页Hot Working Technology

摘　　要：为了研究半固态注射成形技术对AZ91D镁合金显微组织、力学性能以及腐蚀行为的影响,通过对半固态注射成形镁合金进行热处理及电化学腐蚀分析,研究了镁合金成形件在注射成形中与热处理后的组织及性能变化。结果表明,相对于压铸镁合金,半固态注射成形镁合金的组织均匀、力学性能优良、晶粒细小且平均晶粒尺寸为20~30μm,能获得质量良好的显微组织。镁合金的热处理对晶界第二相的数量和分布有较大影响,能作用于材料性能。经时效处理后,镁合金硬度从63.47 HV提高到74.05 HV,抗拉强度从125.56 MPa提高到150.91 MPa,抗拉强度提高了20.2%。在质量分数为3.5%的NaCl溶液的电化学腐蚀中,合金的自腐蚀电位为-959.56 mV,经固溶+时效处理后,自腐蚀电位先升高到-927.55 mV后下降至-988.94 mV,耐腐蚀性能先增高后降低。In order to study the effects of the semi-solid molding technology on its microstructure,mechanical properties and corrosion behavior of AZ91D magnesium alloy,through the heat treatment and electrochemical corrosion analysis of the semi-solid injection-formed magnesium alloy,the microstructure and properties changes of the magnesium alloy forming parts after injection and heat treatment were studied.The results show that compared with the die-cast magnesium alloy,the semi-solid injection magnesium alloy has uniform microstructure,excellent mechanical properties,fine grains and average grain size of 20-30μm,which can obtain good quality microtissue.The heat treatment of magnesium alloy has a great influence on the number and distribution of the second phase at the grain boundary and can act on the material properties.After aging treatment,the hardness of magnesium alloy increases from 63.47 HV to 74.05 HV,and the tensile strength increases from 125.56 MPa to 150.91 MPa,the tensile strength is increased by 20.2%.In the electrochemical corrosion of NaCl solution with a mass fraction of 3.5%,the self-corrosion potential of the alloy is-959.56 m V.After solid solution+aging treatment,the self-corrosion potential first increases to-927.55 m V and then decreases to-988.94 m V,and the corrosion resistance increases first and then decreases.

关 键 词：AZ91D镁合金 半固态注射成形 微观组织 热处理 腐蚀 

分 类 号：TG146.2[一般工业技术—材料科学与工程]