铸锭不均匀化处理对Al-1.01Mg-1.11Si-0.38Cu-0.69Mn合金热轧板显微组织的影响  

Effects of homogenization-free on the microstructures of hot-rolled Al-1.01Mg-1.11Si-0.38Cu-0.69Mn alloy sheets

作　　者：田妮 刘启隆[1] 赵紫研 赵刚 刘坤 

机构地区：[1]东北大学材料科学与工程学院,辽宁沈阳110819 [2]东北大学材料各向异性与织构教育部重点实验室,辽宁沈阳110819 [3]魁北克大学席库提米分校应用科学系

出　　处：《轻合金加工技术》2018年第3期26-32,36,共8页Light Alloy Fabrication Technology

基　　金：十三五国家重点研发计划项目(2016YFB0300801);国家自然基金面上项目(51371045);中央高校基本科研业务费资助(N130410003;L1502023);新世纪优秀人才支持计划项目(NCET-12-0110)

摘　　要：采用金相和SEM/EDS测定分析,对比研究了汽车车身板用DC铸造的Al-1.01Mg-1.11Si-0.38Cu-0.69Mn合金铸锭经常规均匀化处理后再热轧及不经均匀化处理直接加热热轧板材的显微组织。结果表明,DC铸造Al-1.01Mg-1.11Si-0.38Cu-0.69Mn合金铸锭中主要存在AlMgSi、AlCuMgSi和AlFeMnSi三类结晶相。经545 ℃ 24h常规均匀化处理后,黑色AlMgSi相和白亮颗粒状AlCuMgSi相回溶入基体消失,灰色AlFeMnSi相部分溶解收缩、球化、粗化,同时在枝晶晶干内出现大量细小的弥散相粒子。经常规均匀化处理的铸锭及不经均匀化处理的铸锭热轧后结晶相均沿轧向呈碎链状分布,当热轧变形量达到93%时,2.5mm厚热轧板表面及中心层组织大致相同。热轧板再经545 ℃ 2h固溶、水淬处理后结晶相数量均减少且均发生再结晶,然而,与铸锭经均匀化处理后热轧的板材相比,铸锭不经均匀化处理直接热轧的板材中结晶相尺寸更小、数量更多、分布更均匀,板材再结晶不充分。The microstructure of Al-1. 01Mg-1. 11Si-0. 38Cu-0. 69Mn aluminum alloy sheet hot-rolled from the homogenized and homogenization-free ingot were investigated by the optical microscopy and SEM/EDS. The results show that there are three main constituents AlMgSi, AlCuMgSi and AlFeMnSi in the as-cast Al-1.01Mg-1. llSi-0. 38Cu-0.69Mn alumi- num alloy ingot. After homogenized at 545℃ for 24 h, the black AlMgSi and the white bright AlCuMgSi particles in the ingot dissolve into the matrix; the grey AlFeMnSi particles partly dissolve, contract into sphere and become coarse; many ultra-fine dispersoids appear in the dendritic arms. Regarding the sheets hot-rolled from the homogenized and homoge-nized-free ingots, the constituents are both distributed as broken chains along the rolling di- rection. And the microstructure of the surface and the central layer of the 2.5 mm thick hot- rolled sheets are almost the same when the total hot-rolling reduction reaches 93%. The a- mount of constituent decreases and recrystallization occurs in the sheet after solution treated at 545℃ for 2 h and then water quenched. However, compared with the constituent in the sheet hot-rolled from the DC casting ingot after 545 ℃ 24 h homogenizing treatment, the con- stituent in the sheet directly hot-rolled from the DC casting ingot without homogenization is fi- ner, more numerous, more uniform, and with insufficient recrystallization.

关 键 词：Al-Mg—Si—Cu铝合金 汽车车身板 JV均匀化处理 热轧 显微组织 

分 类 号：TG146.21[一般工业技术—材料科学与工程] TG339[金属学及工艺—金属材料]