挤压比对AA8030铝合金棒材组织及电性能的影响  

Effect of extrusion ratio on microstructure and electrical properties of AA8030 aluminum alloy rod

作　　者：郭磊[1,2] 易丹青[1,2] 臧冰[1,2] 王斌[1,2] 刘会群[1,2] 柳公器[3] 

机构地区：[1]中南大学材料科学与工程学院,长沙410083 [2]中南大学教育部有色金属材料科学与工程重点实验室,长沙410083 [3]金杯电工股份有限公司,长沙410083

出　　处：《中国有色金属学报》2013年第8期2083-2090,共8页The Chinese Journal of Nonferrous Metals

基　　金：国家自然科学基金资助项目(51071177)

摘　　要：采用热挤压成型工艺制备AA8030（Al-0.7Fe-0.2Cu）铝合金棒材，通过金相（OM）、扫描电镜（SEM）、透射电镜（TEM）及电导率测量等研究挤压比对合金微观组织及电性能的影响。结果表明：合金在挤压变形过程中发生动态再结晶，且分布于铸态合金中的网状Al6Fe相在挤压过程中转变为Al3Fe相，Al3Fe相能够促进再结晶形核、钉扎晶界、细化合金晶粒。在挤压变形过程中，随着挤压比（λ=6~28）的增大，合金电导率先上升再下降；当λ=13时，合金电导率达到最大值60.8%（IACS）。运用Matthiessen公式计算不同固溶原子含量时合金的电导率，模型预测结果与实验结果吻合良好。计算及实验结果表明：在较低的挤压比（λ=6~17）下，AA8030合金的电性能主要依赖于固溶原子含量的变化；而在较高的挤压比（λ=17~28）下，合金的电性能将受到固溶原子、位错密度及Al 3 Fe相形貌的综合影响。AA8030 aluminum alloy （Al-0.7Fe-0.2Cu） rod was prepared by hot extrusion, and the influences of extrusion ratio on microstructure and electrical properties of alloy were investigated by OM, SEM, TEM and conductivity determination. The results show that the dynamic recrystallization occurs during hot extrusion, moreover, the meshy Al 6 Fe phase is transformed into Al 3 Fe phase after hot extrusion, Al 3 Fe phase promotes recrystallization nucleation, pins grain boundary and refines alloy grain. During hot extrusion, as the extrusion ratio （λ=6-28） increases, the electrical conductivity of alloy increases at first, then decreases, whenλ=13, the electrical conductivity of alloy reaches a maximum value of 60.8%（IACS）. Matthiessen equation was used to calculate the effect of solution atom on the electrical performance of alloy, the model predictions are in good agreement with experimental results. The results indicate that when the extrusion ratio is low （λ=6-17）, the electrical performance of alloy depends on the content of solution atom, at a higher extrusion ratio （λ=17-28）, the electrical performance will be affected by solution atom, dislocation density and morphology of Al 3 Fe phase.

关 键 词：AA8030铝合金 挤压比 电导率 再结晶 

分 类 号：TG376.2[金属学及工艺—金属压力加工]