Effect of Welding Gap of Thin Plate Butt Welds on Inherent Strain and Welding Deformation of a Large Complex Box Structure

• Published in: Materials Vol. 17; no. 9; p. 1934
• Main Authors: Zhang, Liping, Peng, Genchen, Yang, Fan, Meng, Zhengyu, Yuan, Xiaoming, Fan, Yangyang, Li, Wen, Zhang, Lijie
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 01.05.2024
• Subjects: Butt joints; complex structure; Corner joints; Deformation; Deformation effects; FEM simulation; inherent strain; Laser beam welding; laser welding 304L stainless steel; Lasers; Mechanical properties; Numerical models; Oxidation; Plastic deformation; Residual stress; Seam welds; Simulation; Stainless steel; Steel plates; Strain; Tensile stress; Thin plates; Welding; welding deformation; inherent strain; laser welding 304L stainless steel; complex structure; welding deformation; FEM simulation
• ISSN: 1996-1944; 1996-1944
• DOI: 10.3390/ma17091934

In this study, an effective numerical model was developed for the calculation of the deformation of laser-welded 3 mm 304L stainless steel plates with different gaps (0.2 mm, 0.5 mm, and 1.0 mm). The welding deformation would become larger when the welding gaps increased, and the largest deformation values along the Z direction, of 4 mm, were produced when the gap value was 1.0 mm. A larger plastic strain region was generated in the location near the weld seam, since higher plastic deformation had occurred. In addition, the tensile stress model was also applied at the plastic strain zone and demonstrated that a larger welding gap led to a wider residual stress area. Based on the above results, inherent deformations for butt and corner joints were calculated according to inherent strain theory, and the welding formation for the complex structure was calculated with different gaps. The numerical results demonstrated that a larger deformation was also produced with a larger welding gap and that it could reach the highest value of 10.1 mm. This proves that a smaller welding gap should be adopted during the laser welding of complex structures to avoid excessive welding deformation.