含微量Sc和Zr的Al-Cu-Mg-Fe-Ni合金时效行为和拉伸性能
来源期刊：中南大学学报(自然科学版)1999年第3期
论文作者：余琨 李松瑞 黎文献 肖于德
文章页码：78 - 81
关键词：Al-Cu-Mg-Fe-Ni合金;时效行为;拉伸性能;钪;锆
Key words：Al-Cu-Mg-Fe-Ni alloy; aging behavior; tensile property; scandium; zirconium
摘 要：配制了3种不同成分的Al-Cu-Mg-Fe-Ni系实验合金,研究了微量Sc和Zr对该系合金时效行为和拉伸性能的影响.用硬度法测量了合金在200℃和300℃下的时效硬化曲线,用透射电镜观察了合金在淬火及200℃时效不同时间后的显微组织.在室温(20℃),200,250,300℃下测量了合金的拉伸力学性能,用扫描电镜观察了拉伸断口形貌.结果表明:加入微量Sc,Zr后生成的Al3(Sc,Zr)质点均匀弥散分布,有利于合金中另一强化相S′更均匀析出,从而提高了合金的时效硬化效果.由于Al3(Sc,Zr)相具有很好的热稳定性及沉淀强化效果,合金在室温及高温下的强度都有明显提高,而塑性基本保持不变.合金中Cu含量的减少不利于合金强度的提高.
Abstract: Three Al-Cu-Mg-Fe-Ni alloys with different compositions have been prepared. The effects of trace Sc and Zr on the aging behavior and the tensile properties of the alloys were studied. The aging hardening curves of the alloys at 200 ℃ and 300 ℃ were measured with Vicker′s hardness. The microstructures of the alloys in as quenched conditions and aged at 200 ℃ were observed with transmission electron microscopy (TEM). The tensile properties of the alloys at ambient temperature(20 ℃), 200, 250, and 300 ℃ were measured respectively and the fractography of tensile samples were observed with scanning electron microscope (SEM). The results show that the dispersed secondary Al3(Sc,Zr) phase precipitated from α(Al) is coherent with the matrix, so it has strong disperse strengthening effect. The Al3(Sc,Zr) phase can also make the S′ phase precipitate more homogeneously. The strength of the alloys at ambient and elevated temperature increases because of the thermal stability and precipitation strengthening of Al3(Sc,Zr) particles, and the plasticity of the alloys does not decrease. The decreasing of Cu in the alloy does not benefit the strength improvement of alloy.
