压力容器2025，Vol.42Issue(8)：14-23,10.DOI:10.3969/j.issn.1001-4837.2025.08.003
氩弧焊热输入对不锈钢焊缝4.2 K下断裂韧性的影响
Effect of GTAW heat input on fracture toughness of stainless steel welds at 4.2 K
摘要
Abstract
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.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Key words
fusion reactor/austenitic stainless steel/fracture toughness/gas tungsten arc welding(GTAW)/heat input分类
机械制造引用本文复制引用
XIA Haixin,LI Zixin,FU Yang,ZHU Mingliang,LÜ Yingbin,ZHANG Maolong..氩弧焊热输入对不锈钢焊缝4.2 K下断裂韧性的影响[J].压力容器,2025,42(8):14-23,10.基金项目
国家自然科学基金项目(52321002) （52321002）
