( 1. 中南大學(xué) 材料科學(xué)與工程學(xué)院， 長(zhǎng)沙 410083；
2. 邵陽(yáng)學(xué)院 機(jī)械工程系， 邵陽(yáng) 422004；
3. 西南鋁加工廠， 重慶 401326)
摘 要: 通過(guò)力學(xué)性能檢測(cè)、 掃描電鏡和透射電鏡觀察， 研究了不同時(shí)效制度、 不同變形系數(shù)對(duì)7B04鋁合金組織和性能的影響。 結(jié)果表明： 變形系數(shù)為12.5的合金其性能優(yōu)于變形系數(shù)為6.5的合金； 合金的斷裂屬晶內(nèi)韌窩斷裂與沿晶斷裂的混合型斷裂， 合金的KC主要受其δ值的影響并與其δ值有相似的變化趨勢(shì); 合金的完全時(shí)效制度為130, 16h或140℃, 15h， 在此制度下， 合金的σb, σ0.2, δ和KC分別為645.5MPa, 603.0MPa, 11.4%和36.1MPa·m1/2。
關(guān)鍵字: 7B04鋁合金; 時(shí)效; 組織; 性能
（ 1. School of Materials Science and Engineering,
Central South University, Changsha 410083, China;
2. Department of Mechanical Engineering,
Shaoyang Institute, Shaoyang 422004, China;
3. Southwestern Aluminum Fabrication Plant, Chongqing 401326, China）
Abstract: The effects of different ageing system and different deformation coefficient on the microstructure and mechanical properties of 7B04 aluminum alloy were investigated by means of mechanical properties test, SEM and TEM analysis.The results show that the mechanical properties of the alloy with deformation coefficient of 12.5 are higher than those of the alloy with deformation coefficient of 6.5； the fracture of the alloy is in transgranular/intergranular mixed mode and the variety of KC of the alloy resembles the variety of δ of the alloy； the complete ageing system for 7B04 alloy is 130℃, 16h or 140℃, 15h. By the ageing system, the σb, σ0.2, δ and KC of 7B04 alloy are 645.5MPa, 603.0MPa, 11.4% and 36.1MPa·m1/2， respectively.
Key words: 7B04 aluminum alloy; ageing; microstructure; properties
