Sn对AX55铸造合金组织与蠕变性能的影响  

Effect of Sn on microstructure and creep properties of AX55 casting alloys

作　　者：邱克强[1] 彭冠乔 向青春[1] 任英磊[1] QIU Ke-qiang;PENG Guan-qiao;XIANG Qing-chun;REN Ying-lei(School of Materials Science and Engineering,Shenyang University of Technology,Shenyang 110870,China)

机构地区：[1]沈阳工业大学材料科学与工程学院

出　　处：《沈阳工业大学学报》2019年第5期517-523,共7页Journal of Shenyang University of Technology

基　　金：沈阳市科技计划项目(F14-197-4-00)

摘　　要：为了提高Mg-5Al-5Ca(AX55)铸造镁合金基体组织和共晶组织的耐热性能,以Sn为变量设计了AX55-x Sn(x=0,0.5,1.0,1.5)合金,研究了T61和T62对合金组织、硬度与蠕变性能的影响.结果表明,随着Sn含量的增加,合金基体中析出的Al 2Ca相增多,使得α-Mg基体得到强化.在共晶骨架相附近析出的CaMgSn相可使共晶组织得到强化.在175℃/70 MPa蠕变100 h条件下,AX55-x Sn合金的最小蠕变速率和蠕变总量随Sn含量的提高而降低.AX55-1.5Sn合金性能最佳,且其最小蠕变速率为5.21×10^-8 s^-1,100 h总蠕变量为0.065%.相比T61,T62能够提高AX55-x Sn合金的基体硬度和蠕变性能.In order to improve the heat resistance of matrix and eutectic structure of Mg-5Al-5Ca(AX55)cast magnesium alloys,AX55-x Sn(x=0,0.5,1.0,1.5)alloys with the changing Sn content were designed.The influence of T61 and T62 on the microstructure,hardness and creep properties of alloys was investigated.The results show that with increasing the Sn content,the Al 2Ca phase precipitated in the alloy matrix increases,which strengthens theα-Mg matrix.The CaMgSn phase precipitated near the eutectic skeleton phase can strengthen the eutectic structure.After the creep test for 100 h under the condition of 175℃/70 MPa,the minimum creep rate and the total creep amount of AX55-x Sn alloys decrease with increasing the Sn content.The AX55-1.5Sn alloy has the optimum performance,the minimum creep rate of 5.21×10^-8 s^-1 and a total creep amount of 0.065%after the creep test for 100 h.Compared with T61,T62 can effectively improve the matrix hardness and creep properties of AX55-x Sn alloys.

关 键 词：镁合金 热处理 蠕变 析出相 最小蠕变速率 维氏硬度 基体强化 抗蠕变性能 

分 类 号：TG[金属学及工艺]