平板试件孔边塑性区的研究  

Study on the Plastic Zone around the Hole in Flat Plates

作　　者：林高用[1] 张振峰[1] 周佳[1] 郑小燕[1] 杨伟[1] 

机构地区：[1]中南大学材料科学与工程学院,湖南长沙410083

出　　处：《中国材料科技与设备》2007年第5期81-83,共3页Chinese Materials Science Technology & Equipment

基　　金：中南大学“米塔尔”学生创新创业基金资助项目（05M029）

摘　　要：小孔缺陷对受力平板试件的承栽能力有着重要的影响。本文采用应力函数法和叠加原理，推导出了单向拉伸平板试件孔边应力场；利用该应力场公式、主应力公式和Mises屈服方程推导出了孔边塑性区方程，利用Mathematica软件求解出孔边塑性区尺寸-r和θ，并绘出了无限大单向拉伸平板试件的孔边塑性区。采用退火态SUS304—2B不锈钢和热轧态LC52铝舍金两种材料的带孔平板试件进行单向拉伸实验，通过实验结果与上述孔边应力集中理论的分析比较发现，由于塑性钝化使得单向拉伸带孔平板试件的实际承载能力与理论计算存在一定差别。The load bearing capacity of the flat plates is greatly influenced by small-bore defect. By using stress function method and superposition principle, the stress fields around the bore of the uni-axial stretched flat samples are deduced; and based on this stress field formula, primary stress formula and Mises yielding equation, the boundary equation of the plastic zone around the bore of the above sample is also educed. The dimensions, r and θ, of the plastic zone are made out by applying a computational software-Mathematical; and the plastic zone boundary around the bore is drawn. The flat samples of the annealing stainless steel SUS304-2B and the hot-rolled LC52 aluminum alloy with bores are tested by uni-axial tension. By comparing the experimental results with the analytical results of the above theory about stress concentration, it is found that there are some differences in load bearing capacity between the theoretical analysis and test results because of plastic passivation effect at the edge of the bore.

关 键 词：孔边应力集中 孔边塑性区 塑性钝化 单向拉伸 平板试件 

分 类 号：O343.4[理学—固体力学]