中国激光, 2013, 40 (5): 0503007, 网络出版: 2013-04-23
T型接头双侧激光同步焊接特性研究
Study on the Characteristics of Double-Sided Laser Beam Welding for T-Joints
激光技术 T型接头 双侧激光同步焊接 焊缝成形 组织特征 铝合金 laser technique T-joint double-sided laser beam welding weld appearance microstructure characteristics aluminum alloy
摘要
以国产大型客机机身壁板铝合金T型接头双侧激光同步焊接技术的开发为背景,系统地研究了焊接工艺参数与光束姿态对焊缝成形质量的影响,初步探讨了接头的微观组织特征。试验结果表明:采用双侧激光同步焊接方法可以实现机身壁板T型接头的焊接,获得了成形质量良好的接头。激光功率和焊接速度的匹配应使热输入控制在25~35 J/mm之间,同时应匹配合理的送丝速度以保证焊缝表面平滑过渡;在满足熔深及熔合面积要求的前提下,应采用较小的光束入射角度以降低热输入对蒙皮背部的热影响;当光束入射位置偏移桁条0.2 mm左右时,焊缝角度为45°~50°,同时T型接头的拉伸强度达到最大值;必须严格控制光束间距实现双侧熔池相互贯通以保证双侧焊缝对称和提高力学性能。T型接头微观组织存在等轴晶区、柱状晶区、部分熔化区、过热区和母材区等5个特征区域,部分熔化区随着远离焊缝中心越来越窄且蒙皮侧较桁条侧明显。
Abstract
With the development of double-sided laser beam welding technique of aluminum alloy T-joints for domestic aircraft fuselage panels as the ground, the effects of welding parameters and laser posture on the welding seam formation quality are studied in details, and the microstructure characteristics of the T-joints are also preliminarily discussed. The experimental results show that it can realize the welding of T-joints for aircraft fuselage panels by double-sided laser beam welding and can obtain good welding appearance. In order to get adequate weld, the heat input will be controlled between 25 J/mm and 35 J/mm by matching laser power to suitable welding speed. Moreover, the wire feeding speed must be reasonable matched to guarantee the smooth transition of the weld surface. It is better to adopt low incident beam angle under the requests of weld penetration and fusion area, which is good for reducing the heat effects of the heat input. The optimal incident beam position is determined to be 0.2 mm on the stringer yielding a 45°~50° seam angle, and the maximum tensile strength reaches a maximum value. In order to keep the double-sided weld symmetry and improve the mechanical properties of T-joints, the beam separation distances must be strictly controlled to realize the double-sided welds fused in a common molten. Five distinct zones are identified which consist of the cellular dendrite zone, parallel dendrite zone, partially melted zone, over-aged zone, and base material. The partially melted zone become narrower further from the fusion zone center and which on the skin side is obviously than that on the stringer side.
杨志斌, 陶汪, 刘申, 陈洁, 陈彦宾, 李俐群, 陈磊. T型接头双侧激光同步焊接特性研究[J]. 中国激光, 2013, 40(5): 0503007. Yang Zhibin, Tao Wang, Liu Shen, Chen Jie, Chen Yanbin, Li Liqun, Chen Lei. Study on the Characteristics of Double-Sided Laser Beam Welding for T-Joints[J]. Chinese Journal of Lasers, 2013, 40(5): 0503007.