焊接变形预测技术研究进展

Review on prediction of welding distortion

关键词:  焊接变形  热弹塑性  固有应变  有限元  预测

Key words:  welding distortion  thermo-elastic-plasticity  inherent strain  finite element  prediction

摘要:

焊接变形是影响焊接结构质量和生产率的主要问题之一,焊接变形的存在不仅影响着焊接结构的制造过程,而且影响着焊接结构的使用性能。一般认为,焊接过程中材料的不均匀受热、板厚方向的热梯度、材料的局部非协调塑性应变以及焊接残余应力的作用是产生各种焊接变形的根本原因。焊接变形预测方法大都基于有限元分析。文中详述了国内外有关焊接变形预测技术的最新研究进展,具体介绍了热弹塑性有限单元法、固有应变法以及基于传统有限元的优化设计法与人工神经网络模型等先进的焊接变形预测方法。

Abstract:

Welding distortion is one of the critical issues that affect weldment quality and productivity.The existence of welding distortion severely affects not only the manufacturing process but also the service performance of welded structure.There are various kinds of welding distortions such as transverse shrinkage,longitudinal shrinkage,bending,angular distortion and buckling distortion.It is generally agreed that the welding distortion arises from the thermal ununiformity,thermal gradient in the thickness direction,localized incompatible plastic strain during welding and effect of residual stress after welding.The methods of welding distortion prediction are largely based on finite element analysis.In this paper,the newest research developments on prediction of welding distortion at home or abroad are summarized.Traditional finite element methods such as the thermal-elastic-plastic finite element method and the inherent stain method are introduced.Furthermore,the optimization design and artificial neural net (ANN) for welding distortion prediction that based on the traditional FEM are also presented.