锆处理对低合金钢大线能量焊接粗晶区组织与性能的影响

来源期刊：钢铁2011年第4期

论文作者：夏文勇 杨才福 苏航 柴锋 雍岐龙

文章页码：76 - 81

关键词：锆处理； 大线能量焊接； 针状铁素体； 船体钢

Key words：zirconium treatment； large heat input welding； acicular ferrite； ship hull steel

摘    要：采用焊接热模拟和热力学计算相结合的方法,研究了锆处理对低合金高强船体钢大线能量焊接粗晶区组织与性能的影响。结果表明:锆处理钢对钢中形成的氧化物类型、粒度及分布存在显著影响。当钢中锆的质量分数低于85×10^-6时,钢中形成复合的Zr-Ti-O氧化物颗粒。其中锆的质量分数为45×10^-6时,钢中形成等量的钛、锆氧化物,此时氧化物颗粒最为细小,微量锆对含钛氧化物颗粒的细化作用最为明显。锆的质量分数大于85×10^-6时,钢中只形成单一的ZrO₂颗粒。复合Zr-Ti氧化物在低合金高强船体钢大线能量焊接时具有促进晶内针状铁素体的能力,显著地提高钢大线能量焊接粗晶区的低温韧性。

Abstract: Effect of zirconium addition on CGHAZ microstructure and properties of large heat input welding low alloy steels were studied based on welding thermal simulation and thermodynamic calculations.The results show that Zr treatment has great effect on the variety,size and distribution of oxide formed in the steel.Zr-Ti-O composite oxide is formed in the steel when zirconium content is lower than 85×10^-6.Equivalent amounts of Ti-O and Zr-O oxide is formed while zirconium content is equal to 45×10^-6,and the size of oxide is the finest in this present condition.Meanwhile,it indicates that the refinement effect of zirconium treatment on the Ti-bearing oxides is obviously.On the other hand,when zirconium content is larger than 85×10^-6,only ZrO₂ inclusions is formed in the steel.Zr-Ti-O composite oxide can promote the formation of acicular ferrite transformation,which improve the impact toughness of CGHAZ of large heat input welding in high strength ship hull steels.