轨道交通用6005A铝合金疲劳断裂特征分析  

Analysis of Fatigue Fracture Characteristic of 6005A Aluminum Alloy Used in Rail Transit

作　　者：杨丽 耿庆涛 黄健 吴海旭 曲凤娇 王东辉 Yang Li;Geng Qingtao;Huang Jian

机构地区：[1]辽宁忠旺集团有限公司,辽宁辽阳111003

出　　处：《上海电气技术》2023年第3期24-27,共4页Journal of Shanghai Electric Technology

摘　　要：以供货状态下的轨道交通用薄壁复杂断面6005A空心铝合金型材为研究对象,在大气环境下采用轴向加载方式进行疲劳试验,采用扫描电子显微镜进行疲劳断口观察,分析6005A铝合金的疲劳断裂特征。试验结果显示,轨道交通用6005A铝合金疲劳源位置在试样加工的侧面,位于棱角附近,可能与表面铣加工刀痕有关。整个断口可以分为疲劳源区、疲劳扩展区、疲劳瞬断区三大部分。裂纹起源于试样表面,呈点源特征。疲劳扩展区可见明显放射棱线,疲劳瞬断区断面较粗糙。疲劳源区光亮、细滑。疲劳扩展区疲劳条带清晰,扩展中期条带间距较小,后期较大。疲劳瞬断区呈现韧窝特征。The study focuses on the thin-walled complex section 6005A hollow aluminum alloy profile used in rail transit under the supply condition.Fatigue test was carried out under atmospheric environment by axial loading method,and the fatigue fracture was observed by scanning electron microscope to analyze the fatigue fracture characteristic of 6005A aluminum alloy.The test result shows that the fatigue source of 6005A aluminum alloy used in rail transit is located on the side of the sample processing,near the edge,which may be related to the cutting mark of surface milling.The entire fracture can be divided into three parts such as fatigue source zone,fatigue propagation zone,and fatigue transient fracture zone.The crack originates from the surface of the sample and exhibits point source characteristic.Obvious radiative edge can be seen in the fatigue propagation zone,and the cross-section of the fatigue transient fracture zone is relatively rough.The fatigue source zone is bright and smooth.The fatigue band in the fatigue propagation zone is clear,with a smaller spacing between the bands in the middle stage of expansion and a wider spacing in the later stage.The fatigue transient fracture zone exhibits dimple characteristic.

关 键 词：轨道交通 铝合金 疲劳断裂 特征 分析 

分 类 号：U270.4[机械工程—车辆工程]