文献类型：期刊文献

中文题名：氩弧焊热输入对不锈钢焊缝4.2 K下断裂韧性的影响

英文题名：Effect of GTAW heat input on fracture toughness of stainless steel welds at 4.2 K

作者：夏海鑫[1];李子昕[1];付阳[1];朱明亮[1];吕映宾[2];张茂龙[2]

机构：[1]华东理工大学机械与动力工程学院,上海200237;[2]上海电气核电设备有限公司,上海201306

年份：2025

卷号：42

期号：8

起止页码：14

中文期刊名：压力容器

外文期刊名：Pressure Vessel Technology

收录：;北大核心:【北大核心2023】；

基金：国家自然科学基金项目(52321002)。

语种：中文

中文关键词：聚变堆;奥氏体不锈钢;断裂韧性;钨极惰性气体保护焊(GTAW);热输入

外文关键词：fusion reactor;austenitic stainless steel;fracture toughness;gas tungsten arc welding(GTAW);heat input

摘要：针对316LN和316LN-Mn两种不锈钢焊缝超低温断裂韧性低的问题,提出通过建立焊接参数-微观组织-断裂韧性的映射关系优化焊接工艺方案。在3种不同热输入条件下制备了2种钢的焊接接头,并在4.2 K超低温下测试了接头焊缝区的断裂韧性。结合硬度、微观组织及断口形貌分析,研究了热输入、晶粒尺寸与断裂韧性之间的关系。结果表明,随着热输入增加,2种接头的焊缝超低温断裂韧性均先升高后降低,而晶粒尺寸逐渐增大。进一步研究发现,焊缝晶粒尺寸存在一个临界过渡区:当晶粒尺寸小于该过渡区时,尺寸越大,断裂韧性越高;当晶粒尺寸大于该过渡区时,则呈现相反趋势。研究可为焊接参数的选取以及通过焊接热输入快速评估焊缝超低温断裂韧性提供参考。
To address the low ultra?low temperature fracture toughness of welds in 316LN and 316LN-Mn stainless steels,a method to optimize the welding process by establishing a mapping relationship between welding parameters,microstructure,and fracture toughness was proposed.Welded joints of the two steels were prepared under three different heat input conditions,and the fracture toughness of the weld zone was tested at 4.2 K.The relationship between heat input,grain size,and fracture toughness was investigated through analysis of hardness,microstructure,and fracture morphology.The results show that with increasing heat input,the ultra?low temperature fracture toughness of the welds for both joints first increased and then decreased,while the grain size gradually increased.Further study found a critical transition zone for weld grain size:when the grain size is smaller than this zone,larger grain size leads to higher fracture toughness;when the grain size is larger than this zone,the opposite trend is observed.This research provides a reference for selecting welding parameters and quickly assessing the ultra?low temperature fracture toughness of welds based on welding heat input.