氧化物粒子和Nb元素对大热输入焊缝金属显微组织及冲击性能的影响  

Influences of oxide particles and Niobium on microstructure and impact toughness of weld metal with large heat input

作　　者：李丽[1] 罗强 田浩 王红鸿[2] 吴开明[2] 

机构地区：[1]南京钢铁集团有限公司研究院,南京210035 [2]武汉科技大学高性能钢铁材料及其应用湖北省协同创新中心,武汉430081

出　　处：《焊接》2017年第11期10-13,共4页Welding & Joining

基　　金：国家自然科学基金重点资助项目(50734004)

摘　　要：母材焊接时通过交互结晶及成分稀释对焊缝金属的组织和性能产生影响。研究了母材中氧化物粒子及Nb元素对大热输入焊接的焊缝金属显微组织及冲击性能的影响。结果表明,氧化物粒子通过熔合线过渡到焊缝金属中,促进了焊缝金属中针状铁素体的形成。Nb元素细化了熔合线区域的晶粒,使以其为基底结晶的焊缝金属的柱状晶宽度减小。以上两个因素使得含氧化粒子和Nb元素的母材相比较于无氧化物粒子和不含Nb元素的母材,形成的焊缝金属韧性较高。因此,在选用焊接材料时一定要考虑母材的影响。The microstructure and mechanical properties of weld metal were influenced by base metal when the interaction crystallization and the composition dilution occur. The influences of oxide particles and Niobium on the microstructure of weld metal with high heat input welding and its impact toughness were studied. The results showed that the oxide particles can be transited to the weld metal and promote the formation of acicular ferrite in weld metal. Niobium elements can refine the grains of fusion line and decrease the width of columnar crystal in the weld zone. Compared with the parent metal without oxide particles and Niobium,the parent metal with oxide particles and Niobium can form the weld metal with higher toughness. Therefore,the influence of the base metal must be considered in selecting welding material.

关 键 词：大热输入焊接 焊缝金属 NB微合金化 显微组织 冲击性能 

分 类 号：TG443[金属学及工艺—焊接]