摘要
利用DSC、X射线衍射 (XRD)、透射电镜 (TEM)和能谱分析研究了快速凝固Al 5Zn 2 5Mg 2 5Mn(质量分数 )合金急冷态和退火态的显微组织 ,同时测定了该合金的硬度。DSC曲线有四个放热峰 ,位于 90～ 110℃、2 6 0℃、4 6 0℃和 4 80℃ ,它们分别对应于 η相 (MgZn2 )、T相 (Al2 Mg3Zn3)、Al3Mn相和Al6 Mn相的析出或转变 ,分析结果与XRD和TEM分析一致。研究还表明 :快凝合金急冷态组织为过饱和Al基固溶体 ,无其它相存在 ;快凝合金经 30 0℃× 1h处理后 ,出现 η和T相 ,此时无Al Mn相出现 ;快凝合金经 5 0 0℃× 1h处理后 ,出现了Al Mn弥散相 ,而 η和T相溶入固溶体 ,Al的点阵常数和合金硬度变化验证了上述显微组织的演化过程。随着Al Mn相的析出或转变 。
The microstructures of as spun and as annealed ribbons in rapidly solidified Al 5Zn 2.5Mg 2.5Mn (mass,%) alloy were investigated by using differential scanning calorimetry(DSC),X ray diffraction (XRD),transmission electron microscopy(TEM) and energy dispersive spectroscopy (EDS). The hardness of the alloy was also measured by means of Vickers hardness meter.The results showed that there were four exothermic peaks in the DSC curve occurring in the temperature range of 90 to 110℃ and 260 to 280℃ corresponding to precipitation of the η (MgZn\-2) and T (Al\-2Mg\-3Zn\-3) phase respectively,similarly,the exothermic reaction at 460℃ and 480℃ was related to the formation of Al\-3Mn and Al\-6Mn dispersoid,which is consistent with the results of XRD and TEM analysis. The microstructure of the as spun alloy was in supersaturated solid solution state and no second phase in Al matrix. When annealing at 300℃ for 1 hour,there were η and T phase in the matrix and no Al Mn phase.Heat treatment at 500℃ for 1 hour lead to the formation of Al\-3Mn and Al\-6Mn dispersoid and the dissolution of η and T phase.Evolution of microstructure of the alloy was checked and verified by the change of the lattice constant of the Al matrix and the hardness of the alloy. Significant increase in hardness was attributed to the precipitation or transformation of the Al Mn phase.
出处
《材料热处理学报》
EI
CAS
CSCD
北大核心
2002年第2期24-27,共4页
Transactions of Materials and Heat Treatment
基金
安徽省教委自然科学基金资助 (2 0 0 0jl1 72 )
