(1. 中南大學(xué) 材料科學(xué)與工程學(xué)院，長沙 410083;
2. 中南大學(xué) 教育部有色金屬材料科學(xué)與工程重點實驗室，長沙 410083；
3. 金杯電工股份有限公司，長沙 410083)
摘 要: 采用熱擠壓成型工藝制備AA8030(Al-0.7Fe-0.2Cu)鋁合金棒材，通過金相(OM)、掃描電鏡(SEM)、透射電鏡(TEM)及電導(dǎo)率測量等研究擠壓比對合金微觀組織及電性能的影響。結(jié)果表明：合金在擠壓變形過程中發(fā)生動態(tài)再結(jié)晶，且分布于鑄態(tài)合金中的網(wǎng)狀A(yù)l6Fe相在擠壓過程中轉(zhuǎn)變?yōu)锳l3Fe相，Al3Fe相能夠促進再結(jié)晶形核、釘扎晶界、細(xì)化合金晶粒。在擠壓變形過程中，隨著擠壓比(λ=6~28)的增大，合金電導(dǎo)率先上升再下降；當(dāng)λ=13時，合金電導(dǎo)率達(dá)到最大值60.8%(IACS)。運用Matthiessen公式計算不同固溶原子含量時合金的電導(dǎo)率，模型預(yù)測結(jié)果與實驗結(jié)果吻合良好。計算及實驗結(jié)果表明：在較低的擠壓比(λ=6~17)下，AA8030合金的電性能主要依賴于固溶原子含量的變化；而在較高的擠壓比(λ=17~28)下，合金的電性能將受到固溶原子、位錯密度及Al3Fe相形貌的綜合影響。
關(guān)鍵字: AA8030鋁合金；擠壓比；電導(dǎo)率；再結(jié)晶
（1. School of Materials Science and Engineering, Central South University, Changsha 410083, China;
2. Key Laboratory of Nonferrous Metal Materials Science and Engineering, Ministry of Education, Central South University, Changsha 410083, China;
3. Gold Cup Electric Apparatus Co.Ltd., Changsha 410083, China）
Abstract: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 Al6Fe phase is transformed into Al3Fe phase after hot extrusion, Al3Fe 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, when λ=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 Al3Fe phase.
Key words: AA8030 aluminum alloy; extrusion ratio; electrical conductivity; recrystallization
