(1. 武漢鋼鐵（集團(tuán)）公司技術(shù)中心， 武漢 430080；
2. 武漢科技大學(xué)材料系， 武漢 430081)
摘 要: 簡(jiǎn)要敘述了新研制的大線能量焊接低焊接裂紋敏感性調(diào)質(zhì)高強(qiáng)度鋼的特點(diǎn)。 研制的新鋼種屬低碳低合金高強(qiáng)鋼， 集高強(qiáng)度(σs≥490MPa、 σb≥610MPa)、 高韌性(-20℃時(shí)橫向Akv≥47J)、 優(yōu)異的焊接性能（厚度≤50mm鋼板焊前不需預(yù)熱或稍加預(yù)熱而不產(chǎn)生冷裂紋）于一體，并能承受大線能量(≥50kJ/cm)焊接。 研究了模擬焊接熱影響粗晶區(qū)(CGHAZ)的微觀組織結(jié)構(gòu)特征及其與力學(xué)性能的關(guān)系。結(jié)果表明： CGHAZ中復(fù)合夾雜物可促進(jìn)針狀鐵素體的形成，針狀鐵素體的數(shù)量與輸入線能量有關(guān)并顯著影響CGHAZ的力學(xué)性能。
關(guān)鍵字: HSLA鋼； 低焊接裂紋敏感性； 大線能量焊接； 焊接熱影響粗晶區(qū)；微觀組織； 針狀鐵素體
LIU Ji-xiong1, BU Yong1
（1. NETC of Wuhan Iron and Steel(Group) Corporation,
Wuhan 430080, China;
2. Department of Material, Wuhan University of Science and Technology, Wuhan 430081, China）
Abstract:The feature of new developed HSLA steels for large heat input welding with low susceptivity to weld cracking was presented. The steels designated as WDL610D2, which gather high strength(σs≥490MPa, σb≥610MPa), high impact toughness(at -20℃, Akv≥47J) and excellent weldability(the weld crack may be not formed without preheat or preheat with a little heat input for the steel plate with a thickness of less than 50mm), can be welded with large heat input(≥50kJ/cm). The microstructure nature of CGHAZ, which is a function as mechanical properties, was investigated. The complex inclusions in CGHAZ promote the acicular ferrite formation, which is associated with heat input and affects the mechanical properties of CGHAZ.
Key words: HSLA steel; low susceptivity to weld cracking; large heat input welding; coarse grain heat affected zone; microstructure; acicular ferrite
