铸轧速度及镁含量对Al-50Si-xMg合金组织与性能的影响  

The influence of roll-casting speeds and Mg contents on the microstructures and properties of Al-50Si-xMg alloys

作　　者：徐博岳 王金元 许光明[1,2] 王昭东[1,3] XU Bo-yue;WANG Jin-yuan;XU Guang-ming;WANG Zhao-dong(College of Materials Science and Engineering,Northeastern University,Shenyang 110004,China;Key Laboratory of Material Electromagnetic Process Research,Ministry of Education,Northeastern University,Shenyang 110004,China;State Key Laboratory of Rolling and Automation,Northeastern University,Shenyang 110004,China)

机构地区：[1]东北大学材料科学与工程学院,辽宁沈阳110004 [2]东北大学材料电磁过程研究教育部重点实验室,辽宁沈阳110004 [3]东北大学轧制及自动化国家重点实验室,辽宁沈阳110004

出　　处：《轻合金加工技术》2020年第4期16-22,46,共8页Light Alloy Fabrication Technology

基　　金：国家自然科学基金资助项目(51790485)。

摘　　要：采用立式双辊铸轧(VTRC)工艺通过不同的铸轧速度制备了不同镁含量[w(Mg)分别为0、5%、10%]的Al-50Si-xMg合金,同时对所制备合金的微观组织和相组成进行了系统分析,并就初晶Si的中心偏聚以及板材的开裂、分层现象进行了详细的阐述.结果表明:当铸轧速度大于5 m/min时,合金中的初晶Si细小且分布均匀,并且Mg元素的加入会使合金的组织和性能得到进一步改善;但当铸轧速度为2 m/min时,板材心部将会出现由初晶Si的中心偏聚引起的开裂分层现象;当铸轧速度为30 m/min,w(Mg)=10%时,Al-50Si-xMg合金中初晶Si的尺寸能从16.4μm减小到7.0μm,此时合金的硬度达到最大值384 HV.The Al-50Si-xMg alloys with different Mg content[w(Mg)=0,5%and 10%]were prepared by vertical twiroll casting(VTRC)process at different roll-casting speeds.At the same time,the microstructure and phase composition of the alloys were researched in detail.In addition,the central congregation mechanism of primary Si and the cracking and stratification phenomenon of sheets were illuminated systematically.It is found that when the roll-casting speed is higher than 5 m/min,the primary Si is fine and distributed uniformly in the alloy.Moreover,the addition of Mg element could further improve the microstructure and properties of the alloy.However,when the roll-casting speed is 2 m/min,the cracking and stratification phenomenon caused by the centralization of the primary Si will appear in the center of the plate.The size of the primary Si decreases from 16.4μm to 7.0μm and the hardness of the alloy reaches the maximum value of 384 HV when the roll.casting speed is 30 m/min and w(Mg)is 10%.

关 键 词：立式双辊铸轧 Al-50Si-xMg合金 初晶SI 中心偏聚 分层现象 

分 类 号：TG349.9[金属学及工艺—金属压力加工]