摘要
采用搅拌摩擦焊技术对304奥氏体与430铁素体异种不锈钢进行了焊接。分析了不同焊接速度对焊接接头组织结构以及力学性能的影响。结果表明,将304不锈钢置于前进侧,在轴肩下压量0.2 mm,停留时间10 s,800r/min的转速下,采用30 mm/min的焊接速度能获得成形较好的接头,焊核区的铁素体及奥氏体相混合均匀,晶粒细小,形成了良好的机械和冶金结合。随着焊接速度的增加,抗拉强度和伸长率先增加后减小,当焊接速度为30 mm/min时,抗拉强度和伸长率最大,分别达到393.51 MPa和18.59%。拉伸断口在焊缝附近的铁素体不锈钢侧,断口具有韧性断裂特征。
304 austenitic and 430 ferritic stainless steels were welded by friction stir welding. The influence of different welding speeds on the structure and mechanical properties of the welded joints was analyzed. The results indicate that when304 stainless steel is placed on the forward side, plunge depth of the shoulder is 0.2 mm, dwell time is 10 s, rotational speed is800 r/min and welding speed is 30 mm/min, the joint with good formation is obtained. The ferrite and austenite phases mix uniformly, the grains are fine with excellent mechanical and metallurgical bonding in the welding nugget zone. With the increase of welding speed, the tensile strength and elongation increase firstly and then decrease. When the welding speed is 30 mm/min, the tensile strength and elongation reach the maximum, which are 393.51 MPa and 18.59%, respectively. The tensile fracture is located at ferritic stainless steel side near the weld and the fracture is characterized by ductile fracture.
引文
[1]郭国林,杨莉,柳健.激光功率对304不锈钢薄板搭接接头组织和性能的影响[J].热加工工艺,2016,45(8):213-215.
[2]张丽江,张发,朱霞.不锈钢的发展及其焊接接头腐蚀问题[J].内蒙古石油化工,2011(17):66-68.
[3]Aguilar Sara,Tabares Ramón,Serna Claudia.Microstructural transformationsofdissimilaraustenite-ferritestainlesssteelswelded joints[J].Journal of Materials Physics and Chemistry,2013,1(4):65-68.
[4]Mishraa R S,Ma Z Y.Friction stir welding and processing[J].MaterialsScienceandEngineeringR,2005,50:1-78.
[5]Cui L,Yang X Q,Zhou G,et al.Characteristics of defects and tensile behaviors on Friction stir welded AA6061-T4 T-joints[J].MaterialsScienceandEngineeringA,2012,543:58-68.
[6]Xu W F,Liu J H,Chen D L,et al.Change of microstructure and cyclic deformation behavior along the thickness in a friction-stir-weldedaluminumalloy[J].ScriptaMaterialia,2012,66:5-8.
[7]Lienert T J,Stellwag W L,Grimmett B B,et al.Friction stir weldingstudiesonmild steel[J].WeldingJournal,2003,82(1):1-9.
[8]郭国林,王志国,杨君翼.异种不锈钢搅拌摩擦焊对接接头组织和力学性能[J].热加工工艺,2017,46(21):61-63.
[9]Park S H C,Sato Y S,Kokawa H,et al.Corrosion properties in friction stir welded 304 stainless steel[J].Welding in the World,2005,49:63-68.
[10]Sabooni S,Karimzadeh F,Enayati M H,et al.Gas tungsten arc welding and friction stir welding of ultrafine grained AISI 304Lstainless steel:Microstructural and mechanical behavior characterization[J].Materials Characterization,2015,109:138-151.