(中南大学 材料科学与工程学院，长沙 411083)
摘 要: 采用光学显微镜、差热分析、扫描电镜、能谱分析、透射电镜和X射线衍射研究2124铝合金铸态与均匀化态的显微组织演化和成分分布。结果表明：2124铝合金的铸态组织枝晶偏析严重，在晶界存在很多低熔点共晶相，合金中元素Cu，Mg和Mn在晶内及晶界分布不均匀；经过均匀化处理后，2124铝合金组织中的非平衡相逐渐溶解，各组元分布趋于均匀；该合金的过烧温度为504 ℃，最佳均匀化制度为(490 ℃，24 h)，该制度与均匀化动力学方程得到的结论基本一致。
关键字: 2124铝合金；均匀化处理；显微组织；动力学
（School of Materials Science and Engineering, Central South University, Changsha 410083, China）
Abstract:The evolution of the microstructure and the composition distribution of as-cast and homogenized 2124 aluminum alloy were studied by optical microscopy (OM), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), energy dispersive X-ray diffractometry (EDX), transmission electron microscopy (TEM) and X-ray diffractometry (XRD). The results show that serious dendrite segregation exists in the 2124 alloy ingot, and many eutectic phases with low melting-point exist in the grain boundary. Cu, Mg and Mn elements distribute unevenly from the grain boundary to inside of the alloy. The non-equilibrium eutectic phases dissolve after homogenization, and the grain boundary becomes sparse and all elements become more homogenized. The over-burnt temperature is 504 ℃. And the proper homogenizing process of the 2124 alloy is (490 ℃, 24 h), which is corresponding with the results of homogenizing kinetic equation.
Key words: 2124 aluminum alloy; homogenization treatment; microstructure; kinetics
