摘要
基于薄板激光焊失稳数值分析理论,建立了矩形栅格结构的激光点焊仿真模型,通过提取超薄板十字交叉结构激光点焊后固有应变的分布,在栅格结构面外失稳变形模型中计算得到十字交叉接头第一阶正特征值屈曲模态,表现为偏转变形。随着热输入的增大,接头的面外变形量明显增加,且偏转方向改变。对两种焊接顺序下的栅格结构进行特征值屈曲变形分析,发现焊接顺序1条件下第1层薄板接头处有明显的向下偏移,变形挠度为27μm。焊接顺序2下薄板的屈曲特征值较小,此时薄板的整体挠度增大。焊点个数的增多导致失稳变形更容易发生,具体表现为薄板的屈曲特征值持续下降,焊点附近屈曲变形的相互耦合作用会使栅格结构在中间层的面外变形量相比顶部和底部区域有明显增大。
Based on the numerical analysis theory of laser welding instability of thin plate,the simulation model of external instability deformation of rectangular grid structure was established by extracting the inherent strain distribution of ultra-thin plate cross structure after laser spot welding.The first positive eigenvalue buckling mode of the cross joint was calculated,which was shown as deflection deformation.With the increase of heat input,the out-of-plane deformation of the joint increases obviously,and the deflection direction changes.Based on the eigenvalue buckling deformation analysis of the grid structure under two kinds of welding sequence,it was found that there is an obvious downward deviation at the joint of the first thin plate under the condition of welding sequence 1,and the deformation deflection was 27μm.Under the welding sequence 2,the buckling eigenvalue of the thin plate was smaller,and the overall deflection of the thin plate increased.With the increase of the number of solder joints,the instability deformation is more likely to occur,which is shown by the continuous decrease of the buckling characteristic value of the thin plate.The coupling of buckling deformation near the solder joint will significantly increase the out-of-plane deformation of the grid structure in the middle layer compared with the top and bottom areas.
作者
张景祺
林健
雷永平
肖荣诗
李龙
宋征
ZHANG Jingqi;LIN Jian;LEI Yongping;XIAO Rongshi;LI Long;SONG Zheng(Beijing University of Technology,Beijing 100124,China;Taiyuan Aero-Instruments Co.,Ltd.,Taiyuan 030006,China;Capital Aerospace Machinery Corporation Limited,Beijing 100076,China)
出处
《航空制造技术》
CSCD
北大核心
2021年第12期61-69,共9页
Aeronautical Manufacturing Technology
基金
北京市自然科学基金(3212001)
国家重点研发计划(2017YFB1104803)
国家自然科学基金(51005004)。
关键词
激光焊
超薄板
栅格结构
失稳变形
焊接顺序
Laser welding
Ultra-thin plate
Grid structure
Instability deformation
Welding sequence
