(1. 山東大學(xué) 材料液固結(jié)構(gòu)演變與加工教育部重點實驗室，濟(jì)南 250061;
2. Department of Materials Science, Bauman Moscow State Technical University, Moscow 105005, Russia)
摘 要: 采用填絲鎢極氬弧焊(TIG)方法對復(fù)層厚度僅為0.3 mm的Super-Ni疊層復(fù)合材料與18-8不銹鋼進(jìn)行焊接試驗。焊后對焊縫的微觀組織及顯微硬度、熔合區(qū)附近元素分布等進(jìn)行分析。結(jié)果表明：疊層復(fù)合材料與焊縫形成可靠的熔合，Super-Ni復(fù)層側(cè)熔合區(qū)附近的顯微硬度升高(HM190)；18-8不銹鋼側(cè)焊縫的顯微硬度低于不銹鋼母材的，不銹鋼熱影響區(qū)的顯微硬度最高(290 HM)；不銹鋼一側(cè)熱影響區(qū)形成δ鐵素體和碳化物析出；母材與焊縫間形成Fe與Ni元素的明顯過渡，疊層復(fù)合材料側(cè)元素過渡區(qū)域的寬度為80~85 μm，18-8不銹鋼側(cè)元素過渡區(qū)域的寬度約為20 μm；焊接中應(yīng)使鎢極氬弧偏向18-8不銹鋼一側(cè)，以避免Ni復(fù)層的過度燒損。
關(guān)鍵字: 疊層復(fù)合材料；鎢極氬弧焊；顯微組織；元素分布；熔合區(qū)
super-Ni laminated composite and 18-8 steel TIG joint
（1. Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials, Ministry of Education,
Shandong University, Ji’nan 250061, China;
2. Department of Materials Science, Bauman Moscow State Technical University, Moscow 105005, Russia）
Abstract:Super-Ni laminated composite (with 0.3 mm-thick cover layer) and 18-8 stainless steel were welded with filler alloy by tungsten inert gas welding (TIG). The microstructure, microhardness and element distributions in the welding zone were analyzed. The results show that a valid connection forms between the laminated composite and the weld metal, the microhardness (190 HM) near the fusion zone of Super-Ni cover layer side increases. The microhardness of the welding seam region on 18-8 steel side is lower than that of the base metal, and the highest microhardness (290 HM) appears in the heat-affected zone (HAZ) of 18-8 steel. δ ferrite and carbide phase form on the HAZ of 18-8 steel side. The transition of Fe and Ni elements obviously occurs between the base metal and the weld, with 80−85 μm-wide transition zone near the laminated composite side and about 20 μm-wide transition zone near the 18-8 steel side. In the welding process, the welding tungsten arc should be controlled towards the 18-8 steel side to avoid excessive melting loss of the Ni cover layer.
Key words: laminated composite; tungsten inert gas welding; microstructure; element distribution; fusion zone
