窄间隙激光焊接研究现状与存在的问题

Current Status of Research and Problems of Narrow Gap Laser Welding

对于20 mm以上的厚板焊接传统上广泛采用窄间隙埋弧焊、窄间隙熔化极气体保护焊等方法,但其热输入大、变形大等特点限制了其发展。激光焊接具有能量集中、热影响区小、焊接变形小等优势,在厚板焊接方面有更大的优势。文中主要介绍了目前中厚板及厚板窄间隙激光焊接方法中常见的激光自熔焊、激光填丝焊和激光-电弧复合焊的技术特点及其研究现状,分析了窄间隙激光焊在实际应用中存在的问题,如焊接效率不足、热输入过大、焊后变形大、易产生未熔合等。激光-电弧复合焊接具有焊接效率高、熔敷效率高、焊接热损伤低等特点,是适合厚板焊接的方法之一。最后总结和展望了激光焊技术在中厚板制造领域的发展前景。

As a key technology in the manufacturing process of marine engineering equipment,ships,nuclear power pipelines and other fields,the thick plate welding quality determines the safety performance and service life of the equipment.Narrow gap submerged arc welding and narrow gap gas metal arc welding arewidely applied to the welding of plate with the thicknessof more than 20 mm,their higher heat input and high residual stress in the joints limit their application in welding of thick steel plate with high heat sensitivity.Laser welding has the advantages of high energy density,small heat-affected zone,small welding deformation,andsoon,whichis fit for welding of thick steel plate.Laser welding,laser welding with filler wire and laser-arc hybrid welding for narrow gap joint were introduced,their characteristics and problems were analyzed.Among them,laser-arc hybrid welding has the characteristics of higher welding efficiency,higher deposition rate and less thermal damage,which is one of the proper methods to weld thick plate.Atlast,the development prospect of laser welding technology in the weldingmanufacturing of thick plate were summarized and proposed.