5356铝合金半连续铸锭显微组织及力学性能  

Microstructure and mechanical properties of 5356 aluminum alloy ingot by semi-continuous casting

作　　者：马良超 樊建勋[1] 刘红伟[1] 甄立玲[1] 杨昭[2] 史晓城 

机构地区：[1]中国兵器科学研究院宁波分院,浙江宁波315103 [2]中南大学材料科学与工程学院,湖南长沙410083

出　　处：《轻合金加工技术》2014年第10期20-25,共6页Light Alloy Fabrication Technology

基　　金：浙江省国际合作项目(2013C24030)

摘　　要：采用半连续铸造工艺成功制得质量合格的5356铝合金铸锭,并通过金相显微镜、扫描电镜、透射电镜、力学性能测试等手段,对均匀化退火前后铸锭的显微组织及力学性能进行了分析。结果表明,5356铝合金铸态组织主要由α-Al+β-Al3Mg2+其他杂质相组成;Al3Mg2相除沿晶界呈网状分布外,还会以颗粒状在晶内析出;大块相呈不规则多边形,数量较少,主要化学成分为Al、Mg、Ti、Cr;小块相呈鱼骨状,数量相对较多,主要成分为Al、Mg、Fe、Mn;5356铝合金铸锭经均匀化退火后抗拉强度达到315.9 N/mm2,断后伸长率达到30.7%,比均匀化前分别提高了10.4%和27.4%。Acceptable quality of 5356 aluminum alloy ingots were successfully obtained by semi-continuous casting process, and microstructure and mechanical properties of the ingots were analyzed before and after homogenization by the optical microscopy, the scanning electron microscopy, the transmission electron microscopy, the mechanical testing and other methods. The results show that the cast mierostructure of 5356 aluminum alloy is mainly composed of α-Al ＋ β-Al3 Mg2 ＋ other impurity phases ; Al3 Mg/phases not only reticularly distributes a- long the grain boundaries, but also granularly precipitates in the crystal;bulk phases with ir- regular polygons are few and mainly composed of Al, Mg,Ti, and Cr;herringbone phases are small, with a relatively large number, and mainly composed of Al, Mg, Fe, and Mn; after homogenization,the tensile strength of 5356 aluminum alloy reaches 315.9 N/mm2, elongation rate after fracture reaches 30.7% ,respectively improved by 10.4% and 27.4%.

关 键 词：5356铝合金 半连续铸造 显微组织 力学性能 

分 类 号：TG292[金属学及工艺—铸造]