| 2006 №12 (08) | 2006 №12 (02) |
The Paton Welding Journal, 2006, #12, 2-11 pages
Low stress no distortion welding based on thermal tensioning effects for thin materials
Q. Guan, D.L. Guo, C.X. Zhang, J. Li
Beijing Aeronautical Manufacturing Technology Research Institute, Beijing, ChinaAbstract
To prevent welding buckling especially in manufacturing aerospace structures with material thickness less than 4 mm low stress no distortion (LSND) welding techniques have been pioneered and developed at the Beijing Aeronautical Manufacturing Technology Research Institute (BAMTRI). The mechanisms of LSND welding techniques using either the whole cross-section thermal tensioning effect or the localized thermal tensioning effect are described in this paper. The basic idea of LSND welding techniques is to perform active in-process control of inherent plastic (incompatible) strain and stress formation during welding to achieve distortion-free results so that no costly postweld reworking operations for distortion correction is required. Emphasis is given to the finite element analysis to predict and optimize the thermal tensioning techniques for engineering application.
Keywords: welding residual stress, low stress no distortion (LSND) welding, buckling distortion, distortion-free result, thermal tensioning, temperature gradient stretching, heat source-heat sink, finite element analysis
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