稀土Er对Al-Cu-Mg-Ag合金微观组织和力学性能的影响

通过室温拉伸和高温拉伸实验以及金相显微镜、扫描电镜、透射电镜和X射线衍射测试,研究了稀土Er对Al-Cu-Mg-Ag合金微观组织和力学性能的影响。结果表明: Al-Cu-Mg-Ag合金中添加微量Er元素后,合金晶粒尺寸明显减小;Er在Al-Cu-Mg-Ag合金中以Al₈Cu₄Er相存在,没有观察到Al₃Er相;随着Er含量升高,Al-Cu-Mg-Ag合金中Ω相析出受到抑制,进而导致合金的室温和高温力学性能显著下降。

Effect of Er Addition on Microstructure and Mechanical Properties of Al-Cu-Mg-Ag Alloys

The effect of an addition of rare-earth Er on the microstructure and mechanical properties of Al-Cu-Mg-Ag alloys was investigated by tensile tests at room temperature and high temperature, as well as using metallographic microscope, scanning electron microscopy, transmission electron microscopy characterization and X-ray diffraction analysis. The results reveal that a small addition of Er can reduce the grain size of Al-Cu-Mg-Ag alloy; Er in Al-Cu-Mg-Ag alloy exists in the form of Al₈Cu₄Er phase, and no Al₃Er phase is observed; the precipitation of Ω phase is obviously suppressed with the increasing of the Er content, thereby leading to degradation of the mechanical properties of Al-Cu-Mg-Ag alloy at room temperature and high temperature.