Er含量对ZL201A铝合金组织和力学性能的影响

Effect of Er Content on Microstructure and Mechanical Properties of ZL201A Aluminum Alloy

摘要:

通过金相显微镜、扫描电子显微镜、透射电子显微镜、能谱仪分析和力学测试，研究了添加Er对ZL201A铝合金的微观结构和力学性能的影响。结果表明，Er的加入使α-Al基体从柱状晶粒转化为细小的等轴晶粒，同时θ相（Al₂Cu）从细小的网络结构转变为弥散细小颗粒结构。当Er含量达到0.4%（质量分数）时，晶粒细化效应达到最大，合金的力学性能最佳；α-Al的平均晶粒尺寸为19 μm；抗拉伸强度和伸长率分别为298.14 MPa和6.56%；断裂模式从脆性断裂转变为韧性-脆性断裂，有利于铝合金的实际应用。当Er含量超过0.4%（质量分数）时，合金的晶粒尺寸增大，力学性能下降。

Abstract:

The effects of Er addition on the microstructure and mechanical properties of ZL201A aluminum alloy were studied via metallographic microscope, scanning electron microscope, transmission electron microscope, energy dispersive spectrometer, and mechanical property tests. Results show that the Er addition can refine the α-Al matrix from columnar grains into fine equiaxed grains. Additionally, the θ phase (Al₂Cu) is transformed from fine network structure into the dispersed fine particle structure. When the Er content reaches 0.4wt%, the grain refinement effect reaches the maximum state and the mechanical properties of the alloy are optimal. The average grain size of α-Al matrix is 19 μm; the tensile strength and the elongation are 298.14 MPa and 6.56%, respectively. The fracture mode also changes from brittle fracture to ductile-brittle fracture, which is beneficial to the practical application of aluminum alloys. When Er content exceeds 0.4wt%, the grain size increases and the mechanical properties of alloy decrease.