摘要
湘钢试生产的耐大气腐蚀气体保护焊丝钢TH550-NQ-Ⅱ制成的实芯焊丝,熔敷金属性能实验结果显示,-40℃低温冲击功不能完全满足AKV≥60 J的要求。本文通过对焊缝横截面进行金相分析,以及对影响低温冲击韧性的因素进行分析,找出造成低温冲击功偏低的主要原因是焊缝存在细小气孔以及针状铁素体分布不够均匀且较为粗大。针对这些原因,设计并试验了添加适量钛元素和提高适量镍含量两种改善方案,-40℃低温冲击功均能满足AKV≥60 J的要求,且能达到AKV 130 J以上。综合考虑改善成本等因素,选择添加适量钛元素进行后续生产。
The solid core welding wire produced by Xiangtan Iron and Steel Co.is made of TH550-NQ-Ⅱatmospheric corrosion resistant gas shielded welding wire steel.Its deposited metal experimental results show that the-40℃impact energy can not meet the requirements of AKV≥60 J.This paper analyses the cross-section of weld seam and the factors influencing low temperature impact toughness by means of metallographic analysis.It is found that the main reasons for the insufficient low impact energy are the pinholes in the weld seam,coarse acicular ferrite and its nonuniform distribution.For these reasons,two improvement schemes are designed and tested,one is adding proper amount of titanium,another is increasing proper amount of nickel.With each one of the above changes,low temperature impact energy at-40℃can meet the requirements of AKV≥60 J and even get more than AKV 130 J.Regard to cost and other factors,adding appropriate amount of titanium elements was chosen for subsequent production.
作者
杨瑞文
罗卫国
陈立
余刚
YANG Ruiwen;LUO Weiguo;CHENG Li;YU Gang(Xiangtan Iron and Steel Co.,Ltd.of Hunan Valin,Xiangtan 411101,China)
出处
《金属材料与冶金工程》
CAS
2019年第6期20-24,29,共6页
Metal Materials and Metallurgy Engineering
