Cr元素对Al-Mg-Si-Cu铝合金组织与性能的影响  

Effects of Cr on Microstructure and Properties of Al-Mg-Si-Cu Aluminum Alloy

作　　者：张新明[1,2] 周志乐[1,2] 唐建国[1,2] 柯彬[1,2] 胡继龙[1,2] 欧阳惠[1,2] 

机构地区：[1]中南大学材料科学与工程学院,长沙410083 [2]有色金属材料科学与工程教育部重点实验室,长沙410083

出　　处：《材料工程》2013年第12期49-53,58,共6页Journal of Materials Engineering

基　　金：国家重大基础研究项目资助(2012CB615900);广东省产学研项目资助(2010A090200078)

摘　　要：采用光学显微镜、扫描电镜、透射电镜、硬度测试、拉伸测试等方法研究Cr元素对Al-Mg-Si-Cu铝合金组织与性能的影响。结果表明:Cr元素可以细化合金的铸态组织,促进β-AlFeSi相向α-AlFeSi相转变,并与基体结合形成Al7Cr化合物等弥散相,显著抑制合金再结晶的产生及其晶粒长大。随着Cr含量的增加,合金的强度与塑性得到了显著的提高。当Cr含量超过0.20%(质量分数)时,合金的强度和塑性却出现了一定程度的降低。这主要是由于Cr元素与Fe,Si元素结合形成大量的AlFeCrSi相,减少了合金中Mg2Si相的析出,减弱了合金的时效强化效果。The effects of Cr on the microstructures and properties of A1-Mg-Si-Cu aluminum alloy were studied by hardness test, tensile test, TEM, SEM and energy spectrum analysis. The results show that Cr addition promotes the phase transition from ^-A1FeSi to a-A1FeSi. The formation of A17 Cr dis- persion phase inhibits the generation and growth of recrystallization. However, Cr and Fe, Si element prior form the combination of A1FeCrSi phase, make the main limitation precipitated phase （Mg2Si） reduce, weaken the strengthening effect. With the increasing of Cr content, the strength and plastici- ty of the alloy increase, when the Cr content is more than 0.20% （mass fraction）, the strength and the plasticity of the alloy reduce in a certain degree. It is mainly due to the combination of Cr, Fe and Si elements and formation large number of A1FeCrSi phase, which reduces the precipitation of Mg2Si phase in the alloy and weakens the ageing treatment effects.

关 键 词：Al-Mg-Si-Cu铝合金 CR含量 组织 力学性能 

分 类 号：TG146.2[一般工业技术—材料科学与工程]