AFA 3G燃料棒下端塞电子束焊产生气胀的分析

宜宾核燃料元件厂在AFA 3G燃料棒首次产品合格性鉴定中发现，大批下端环缝焊产生了气胀的焊接缺陷。本文分析了产生气胀缺陷的原因，并介绍了针对其原因进行的各种试验。结果表明，改变焊接参数，即提高焊接速度和适当控制电子束流强度，是解决燃料棒焊接气胀缺陷的最好途径。

Analysis of Undercutting on EBW Girth Weld of Bottom End Plug for AFA 3G Fuel Rod

A number of undercut defects appeared on the electron beam welding (EBW) girth welds of bottom end plugs during product qualification of the first lot of AFA 3G fuel rod in Yibin Nuclear Fuel Element Plant. This paper presents the analysis of the undercutting causes and the numerous tests have been done. The results show that modifying welding parameters, i.e. speeding rotation rate of the tube and limiting EB current intensity properly, is a desirable way to avoid the undercut defect during welding of fuel rods.