摘要
利用光学显微镜(OM)、差热分析(DSC)、电子探针(EPMA)、扫描电镜(SEM)、能谱分析(EDS)、X射线衍射(XRD)等方法,研究了2055铝-锂合金在均匀化前后的显微组织演变和成分分布。结果表明,2055铝-锂合金的铸态组织为典型的枝晶组织,低熔点共晶相富集在晶界处,Cu、Mg、Ag、Mn、Zn等合金元素在晶内、晶界都存在偏聚;经过均匀化处理后,铸态组织中非平衡共晶相逐渐溶解,晶界内外元素分布均匀,仅有少量高熔点相残留。合理的均匀化制度为500℃24 h,与均匀化动力学方程得到的结果基本一致。
The microstructure evolution and element distribution variation of 2055 Al-Li alloy during homogenization treatment were studied by means of optical microscope （OM）, differential scanning calorimeter （DSC）, electron probe micro-analyze （EPMA）, scanning electron microscope （ SEM ）, energy dispersive spectroscopy （ EDS）, and X-ray diffraction （XRD）. The results show that dendritic structure is typical in as-cast 2055 Al-Li alloy, and eutectic phases with low melting points distribute mainly at grain boundaries. The Cu, Mg, Ag, Mn and Zn elements segregate in grains, at grain boundaries. After homogenization treatment,non-equilibrium eutectic phases in as-cast structure dissolve gradually; elements distribute uniformly and only a small amount of residual phases with high melting points exist. The reasonable homogenization process is 500℃ 24 h, which is in good agreement with the results derived from homogenization kinetic analysis.
出处
《轻合金加工技术》
CAS
北大核心
2016年第7期15-21,共7页
Light Alloy Fabrication Technology
