预拉伸对7075铝合金厚板残余应力分布的影响  

Influence of pre-stretching on residual stress distribution in 7075 aluminum alloy thick-plate

作　　者：龚海[1] 吴运新[1] 廖凯[1] 

机构地区：[1]中南大学机电工程学院,湖南长沙410083

出　　处：《材料热处理学报》2009年第6期201-205,共5页Transactions of Materials and Heat Treatment

基　　金：国家重点基础研究发展计划(2005CB623708)

摘　　要：运用有限元法对7075铝合金厚板预拉伸过程进行了数值模拟,获得了预拉伸板内部的残余应力分布,研究了预拉伸量对残余应力演变的影响。采用裂纹柔度法对淬火板和预拉伸板(拉伸量分别为1.8%、2.2%和2.5%)进行了残余应力检测,计算得到了不同工艺下铝厚板内部的残余应力分布。结果表明:预拉伸能够大幅消减淬火残余应力,当拉伸量为2.2%左右时,残余应力减少至±20MPa,能够满足后续加工的要求。A pre-stretching process of 7075 aluminum plates was simulated using FEM method and stress distributions in the pre-stretched plates were obtained.The influence of stretching ratio on residual stress evaluation was also studied.Taking use of crack compliance method,through-thickness residual stress profiles in quenched aluminum plates and pre-stretched plates with different stretching deformation（1.8%,2.2% and 2.5%） were measured.The results show that the residual stresses decrease greatly after pre-stretching.When quenched aluminum plates were pre-stretched by about 2.2%,the residual stresses decrease to ±20MPa,which satisfy the requirement for machining.

关 键 词：铝合金 残余应力 预拉伸 裂纹柔度法 

分 类 号：TG146.2[一般工业技术—材料科学与工程]