CAJ | 학술논문

采用光学显微镜（OM）、扫描电子显微镜（SEM）、能谱分析（EDS）及差热分析（DSC）研究了7068高强高韧铝合金均匀化热处理制度及其微观组织演变；通过单向拉伸试验及四探针电阻率法测定了不同均匀化后 T6态合金的拉伸性能及电导率。结果表明：7068铝合金铸态组织存在枝晶偏析，非平衡共晶相沿晶界呈连续网状分布，低熔点共晶相初始溶解温度为467.3°C；合金经455°C ×16h ＋465°C ×4h ＋475°C ×4h 三级均匀化处理后，成分均匀，残留共晶很少且 T6态的抗拉强度、延伸率以及电导率均达到所做均匀化处理中最佳，分别为715MPa、13．3％和34．5％IACS。
채용광학현미경（OM）、소묘전자현미경（SEM）、능보분석（EDS）급차열분석（DSC）연구료7068고강고인려합금균균화열처리제도급기미관조직연변；통과단향랍신시험급사탐침전조솔법측정료불동균균화후 T6태합금적랍신성능급전도솔。결과표명：7068려합금주태조직존재지정편석，비평형공정상연정계정련속망상분포，저용점공정상초시용해온도위467.3°C；합금경455°C ×16h ＋465°C ×4h ＋475°C ×4h 삼급균균화처리후，성분균균，잔류공정흔소차 T6태적항랍강도、연신솔이급전도솔균체도소주균균화처리중최가，분별위715MPa、13．3％화34．5％IACS。
The paper presented the effect of homogenization heat treatment on microstructure of 7068 aluminum al oy using OM,SEM-EDS and DSC;it highlighted tensile properties and conductivity of the al oy in the T6 state after three-step homogenization. The results indicated that before homogenization: dendritic segregation in as-cast microstructure, nonequilibrium eutectic phase distribution along the grain boundary,467.3℃ for initial temperature of eutectic phase dissolution;after the homogenization processes of 455℃ ×16h +465℃ ×4h +475℃ ×4h:uniform in composition,tiny eutectic structures;the tensile strength,elongation and conductivity respectively reached 715MPa,13.3% and 34.5% IACS,an optimal state in homogenization .