高导耐热铝合金导线的人工时效及其低周疲劳性能  

Artificial aging and low cycle fatigue performance of high-conductivity heat-resistant aluminum alloy wire

作　　者：方振邦 王若民 李宸宇 缪春辉 滕越 陈国宏 汤文明[2] FANG Zhen-bang;WANG Ruo-ming;LI Chen-yu;MIAO Chun-hui;TENG Yue;CHEN Guo-hong;TANG Wen-ming(Electric Power Research Institute,Anhui Electric Power Co Ltd,State Grid,Hefei 230601,China;School of Materials Science and Engineering,Hefei University of Technology,Hefei 230009,China)

机构地区：[1]国网安徽省电力有限公司电力科学研究院,安徽合肥230601 [2]合肥工业大学材料科学与工程学院,安徽合肥230009

出　　处：《材料热处理学报》2022年第2期41-48,共8页Transactions of Materials and Heat Treatment

基　　金：国家电网有限公司总部科技项目资助(5500-202028257A-0-0-00)。

摘　　要：针对某国产61.5%IACS高导耐热铝合金导线,开展了150~200℃人工时效及5000次应力循环低周疲劳试验,采用拉伸力学性能测试及断口分析探讨了其力学性能的变化规律,评价其服役可靠性。结果表明:该铝合金导线线股时效经历了欠时效、峰时效及过时效3个阶段。在欠时效和峰时效阶段,线股的强度有所提升,而在过时效阶段,其强度下降,但总体上塑性变化不明显。时效铝合金导线线股在低周疲劳过程中产生明显的循环硬化效应,其总应变范围随着应力循环次数增大而降低,2000次应力循环后趋于稳定。第二相析出长大是影响时效铝合金导线线股热稳定性和疲劳性能的关键因素。即便如此,人工时效及低周疲劳后,线股仍具有90%以上的强度保持率,韧窝聚集型断口特征不变,服役可靠性优良。Aiming at a domestic 61.5%IACS high-conductivity heat-resistant aluminum alloy wire,artificial aging at 150-200℃and low cycle fatigue test of 5000 stress cycles were carried out.The variation law of mechanical properties of the aluminum alloy wire was discussed by tensile mechanical property test and fracture analysis,and its service reliability was evaluated.The results show that the aging of the aluminum alloy wire strand has experienced three stages:under aging,peak aging and over aging.In the under aging and peak aging stages,the strength of the aluminum alloy wire strand increases,while in the over aging stage,the strength decreases,but the plastic change is not obvious in the whole aging stage.During low-cycle fatigue test,the cyclic hardening effect of the aged aluminum alloy wire strand is obvious,its total strain range decreases with the increase of the number of stress cycles,and tends to be stable after 2000 stress cycles.The precipitation and growth of the second phase is the key factor affecting the thermal stability and fatigue properties of the aged aluminum alloy wire strand.Even so,after artificial aging and low cycle fatigue,the strength of the aluminum alloy wire strand remains more than 90%of the original strength,the fracture characteristics of dimple aggregation remain unchanged,and the service reliability is excellent.

关 键 词：高导耐热铝合金导线 人工时效 低周疲劳 力学性能 

分 类 号：TG146.2[一般工业技术—材料科学与工程]