Zr-Ti复合脱氧对低碳高强钢大线能量焊接粗晶区韧性的影响  

Effect of Zr-Ti combined deoxidation on toughness of coarse-grained heat-affected zone with high heat input welding of low carbon high strength steels

作　　者：安正源[1] 吴开明[1] 卢伟煜[1] 王红鸿[1] 万响亮[1] 姚永宽[2] 王道远[2] 

机构地区：[1]武汉科技大学国际钢铁研究院,湖北武汉430081 [2]南京钢铁集团有限公司,江苏南京210035

出　　处：《材料热处理学报》2013年第7期106-111,共6页Transactions of Materials and Heat Treatment

基　　金：国家自然科学基金重点项目(50734004)

摘　　要：通过光学显微镜和电子显微镜对比分析了Zr-Ti复合脱氧和传统Al脱氧两种脱氧方式低合金高强度钢在大线能量埋弧焊条件下焊接热影响区粗晶区的组织,研究了两种脱氧方式对粗晶区低温冲击韧性的影响。结果表明:经过Zr-Ti复合脱氧处理后,低合金高强度钢中形成了许多细小弥散的Zr-Ti复合氧化物粒子,这些粒子具有高温稳定性,在焊接过程中起到了钉扎焊接热影响区粗晶区奥氏体晶界移动来抑制晶粒长大和促进针状铁素体形成,所以在较大的埋弧焊焊接线能量(51 kJ/cm)条件下改善了钢板的低温冲击韧性。Microstructure of coarse-grained heat-affected zone of two steels,which were deoxidized by Zr-Ti and Al,respectively,were examined using optical and electron microscopy.Effect of the microstructure formed in the coarse-grained heat-affected zone under the condition of high efficient submerged arc welding on low temperature impact toughness was investigated.Experimental results show that many fine dispersed Zr-Ti composite oxides are observed in the base metal of the steel deoxidized by Zr-Ti.These particles have a good stability at higher temperatures,which exhibit a pinning effect on austenite grains in the coarse-grained heat-affected zone and promote the formation of acicular ferrite.Therefore,the low temperature impact toughness of the coarse-grained heat-affected zone of the steel deoxidized by Zr-Ti is enhanced when the steel is welded with a high heat input of 51 kJ/cm.

关 键 词：Zr-Ti复合脱氧 焊接热影响区 低温冲击韧性 奥氏体晶粒尺寸 针状铁素体 

分 类 号：TG142.33[一般工业技术—材料科学与工程] TG113.26[金属学及工艺—金属材料]