铍电子束环形焊件残余应力测试方法及其数值模拟研究  

Evaluation of Residual Stresses on Beryllium Ringlike Welded Workpieces by Modified-ψ and Various Wavelengths Methods and Finite Element Analysis(In Chinese)

作　　者：陈勇忠[1] 董平[1] 柏朝茂[1] 秦有均 

机构地区：[1]中国工程物理研究院,成都610003

出　　处：《中国核科技报告》2000年第1期215-237,共23页China Nuclear Science and Technology Report

摘　　要：推导了 Modified-ψ 法应力测试及其穿透深度的计算公式,并利用它测试了铍环形焊件热影响区和基体材料中的残余应力。对电子束焊接的铍环其焊缝附近外表面为拉应力,内表面为压应力。由于 Modified-ψ 法透入深度太大,不能用来测定铍的表层残余应力,引入多波长法成功地测试出了铍环表层的应力及应力随层深的分布。同时针对电子束焊接过程的特点,编写了用于应力场计算的有限元分析程序。运用编写的程序分别对不同尺寸及焊接工艺的三个铍环电子束焊接样品进行了有限元分析,并将计算结果与实测值进行了比较。结果表明:有限元计算结果与实测值吻合得较好,为先期预测焊件中残余应力的大小和分布从而优化焊接工艺提供了参考依据。The equations of the X-ray stress measurement by Modified-ψ method and its penetration depth were completely deduced. And it was employed to determine the stresses of heat affected zone and base metal on beryllium ringlike welded workpieces. The results showed that to the beryllium rings the stresses near weld line were tension stresses on external surface but compression stresses on internal surface. The Modified-ψ method could not determine the stresses on the surface layer of beryllium due to its deep penetration depth (about 1 millimeter), so the X-rays of various wavelengths method was introduced to measure the surface stresses and stress distributions with depth of beryllium ringlike welded workpieces. To obtain a quantitative comparison with the experimental data, a plasto-elastic finite element model was developed according to the characteristic of the electron beam welding. The comparison results indicated that the finite element calculations were in good agreement with the general trend of the experimental data so that the model could be used as a guide to optimize the welding parameters by calculation of the residual stresses and stress distributions in the beryllium ringlike welded workpiece.

关 键 词：铍环 多波长法 环形焊 残余应力测试 焊缝 有限元计算 外表面 实测值 轴向应力 数值模拟研究 

分 类 号：TL[核科学技术]