Mg-8.07Al-0.53Zn-1.36Nd镁合金微观组织及裂纹演变行为

发布时间：2018-05-08 09:36

本文选题：Mg-Al-Zn-Nd合金 + 微观组织　；参考：《稀有金属材料与工程》2017年03期

【摘要】：利用XRD、SEM、TEM、EDS等测试方法对Mg-8.07Al-0.53Zn-1.36Nd镁合金微观组织结构进行表征与分析,并采用原位拉伸试验研究了合金显微组织对裂纹萌生及扩展行为的影响。结果表明:试验合金组织中主要包括α-Mg基体,β-Mg_(17)Al_(12),α+β共晶相,Al_(11)Nd_3针状相和Al_2Nd颗粒相。Al_2Nd存在孪晶结构,孪晶面为{11 1},Al_(11)Nd_3存在连续的凹凸界面结构。合金室温原位拉伸试验结果表明:裂纹主要在粗大的β-Mg_(17)Al_(12)相内部萌生,裂纹扩展方式包括沿晶扩展和穿晶扩展。裂纹穿晶扩展主要归因于沿晶界分布的Al_(11)Nd_3、Al_2Nd相与周围组织界面结合能力较强,Al_(11)Nd_3凹凸界面对基体与共晶组织的啮合作用显著。
[Abstract]:The microstructure of Mg-8.07Al-0.53Zn-1.36Nd magnesium alloy was characterized and analyzed by means of XRDX SEM-TEMX EDS and the effect of microstructure on crack initiation and propagation behavior was studied by in-situ tensile test. The results show that there are mainly 伪 -Mg matrix in the microstructure of the tested alloy, 尾 -MgS17 / Altix, 伪尾 eutectic phase and 伪尾 eutectic phase respectively. There are twin structures in the acicular phase of the 伪尾 eutectic phase, the needle-like phase of the Al_2Nd particle phase and the particle phase of the Al_2Nd particle phase. The twin plane is {111} Alspinel, and there is a continuous concave and convex interface structure in the twinning plane. The results of in-situ tensile test at room temperature show that the crack initiation occurs mainly in the coarse 尾 -MgS _ (17) Alp _ (12) phase, and the crack propagation modes include intergranular and transgranular propagation. The propagation of the crack is mainly attributed to the strong binding ability of Alti11Nd3Al2ND phase distributed along grain boundary to the interface of the surrounding structure. The interfacial meshing between matrix and eutectic structure is remarkable.
【作者单位】：内蒙古工业大学;
【基金】：内蒙古自治区自然科学基金项目(2015MS0526) 国家自然科学基金项目(11362014) 高等学校博士学科点专项科研基金(博导类)(20131514110004)
【分类号】：TG146.22

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