摘要
采用数值模拟和试验方法研究动态外拘束对焊接变形的影响。建立包含夹具、压板、工作台和焊接件的三维多体耦合有限元模型,以一定刚度的弹簧单元模拟夹具对焊接件的弹性夹紧,弹簧单元施加初始位移实现夹具对焊接件的预压紧;以焊接件、压板和工作台的接触关系实现压板和工作台对焊接件的动态拘束。结果表明:对焊接件的拘束力在焊接过程中是动态变化的,其变化趋势和焊接件的z向位移变化趋势相同;焊接件初始拘束力影响焊接变形;采用多体耦合模型计算焊接件的动态拘束力和动态变形结果和实测结果吻合良好。
The dynamic distortions with restraints are investigated by using 3D multi-body coupling numerical simulation. A multi-body coupling finite element model including clamp, clamping strip, worktable and welding piece is developed to perform the numerical simulation. In the model, spring elements with specified stiffness are adopted to simulate the elastic clamps, displacement constraints are imposed on the spring elements to implement the clamping of the welding piece before welding, and the contact conditions among welding piece, clamping strip and worktable are used to reflect the dynamic constraint imposed on the welding piece. The results of numerical simulation and experiment show that the clamping force is dynamic during welding, the variety of the clamping force is similar to that of welding distortion in z direction, and the clamping force before welding affects the distortion of welding piece after welding. The simulation results of multi-body coupling finite element model agree well with the experimental ones.
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2010年第6期83-86,92,共5页
Journal of Mechanical Engineering
基金
国家自然科学基金(50875200)
中国机械工程学会焊接学会创新思路预研(07-12-003)资助项目
关键词
焊接变形
动态拘束
三维有限元
多体耦合
Welding distortion Dynamic restraints 3D finite element Multi-body coupling
