Buckling distortion investigation during thin plates butt welding with considering clamping influence

Abstract

Welding induced buckling is generally considered as the most complicated type of out-of-plane welding distortion during thin plate section fabrication, which will significantly influence the fabrication accuracy and cost. Thin plates of 3 mm thickness with dissimilar materials were experimentally butt welded together beforehand, while clamping constraint by fixture jig and additional plate was employed. After cooling down and clamping release, out-of-plane welding distortions were measured, and characteristic of welding buckling behavior can be observed. Advanced thermal elastic plastic (TEP) FE computation with solid elements models of examined butt-welded joints were then carried out. Welding induced buckling can be represented without considering clamping constraint, while much larger difference between computed results and measurement data was obtained. When the influence of clamping constraint employed during welding experiment was considered, good agreement for both deformed tendency and magnitude of out-of-plane welding distortion can be represented. With the clarification of mechanism based on the comparison of longitudinal residual stress, plastic strain as well as shrinkage force, clamping can significantly reduce magnitude of out-of-plane welding distortion, which still could not avoid the occurrence of welding induced buckling, as well as the change of deformed shape pattern.