Gd对Al-Cu-Gd合金微观组织与力学性能的影响

Effects of Gd contents on microstructure and mechanical properties of Al-Cu-Gd alloy

为改善铝铜合金铸件的综合性能,采用电阻炉熔炼制备Gd含量不同的Al-Cu-Gd合金,经金相显微镜、扫描电子显微镜、X射线衍射仪、万能拉伸试验机和布氏硬度计测试分析,研究稀土元素Gd含量对合金微观组织和力学性能的影响。结果表明:当稀土Gd的质量分数从0增加到0.3%,合金显微组织得到细化,达到0.3%时,细化效果最优,合金的硬度和抗拉强度及伸长率均达到最佳;当稀土Gd的质量分数达到0.5%时,合金的晶粒细化不明显,合金的硬度和抗拉强度及伸长率均降低。

This paper is aimed at improving the microstructure and mechanical properties of aluminum-copper alloy castings. The study works towards preparing Al-Cu-Gd alloy containing different Gd content by a resistance furnace; and investigating the effects of rare earth elements Gd content of the alloy on the microstructure and mechanical properties using optical microscopy,scanning electron microscopy,X-ray diffraction,a universal tensile tester,brinell hardness testing instruments. The results show that a0 to 0. 3% increase in mass fraction of Gd could refine the alloy microstructure; a 0. 3% increase may afford an optimal refinement effect,together with the resulting optimal hardness,tensile strength and elongation of the alloy; and a 0. 5% increase may give a modest refinement,reducing hardness,tensile strength and elongation of the alloy.