Method for rapidly predicting welding seam movement in deep-drawing forming process of laser tailor-welded blank

Abstract

The invention discloses a method for rapidly predicting welding seam movement in a deep-drawing forming process of a laser tailor-welded blank. The method comprises steps as follows: 1), a workpiece is dispersed to form triangle elements, formed part grids are obtained, and a virtual work equation is established for final configuration of a plate material; 2), a finite element equation of a one-step simulation method is established; 3), an iterative equation is established by adopting a Newton-Laplace method with convergence factors; 4), the iterative equation is solved; a non-linear equation set is obtained, and a second iterative equation is established by adopting the Newton-Laplace method with convergence factors; the second iterative equation is solved to obtain an initial displacement field; the process is transferred to the step 3), and tailor-welded blank grids obtained through back calculation can be output after Newton-Laplace iterative convergence; 5), two space curves 11 and 12 are obtained by connecting nodes of the elements in welding seams of the formed part grids and the tailor-welded blank grids obtained through back calculation; 6), the two space curves 11 and 12 are projected to the X-Y plane respectively so as to obtain two plane curves 1'1 and 1'2; the welding seam offset is calculated.

Description

technical field [0001] The invention relates to a method for predicting weld seam movement, in particular to a method for quickly predicting weld seam movement during the deep drawing forming process of a laser tailor welded blank. Background technique [0002] In order to reduce the weight of the body, improve the assembly accuracy of the body, increase the rigidity of the body, and reduce the stamping and assembly costs in the manufacturing process of the automobile body, it is necessary to reduce the number of body parts and integrate them. Therefore, a production form that overcomes the shortcomings of the traditional separate forming method and the integral forming method at the same time - stamping forming of tailor welded blanks has been developed. Tailored welded blanks refer to cutting cold-rolled steel sheets of different or the same thickness, strength, and material into appropriate sizes and shapes, and then laser welding them into an ideal whole. Automobile man...

AI Technical Summary

Problems solved by technology

[0003] Although the use of tailor-welded blanks has brought many benefits, there are also many technically difficult problems to solve at the same time, the most important of which are the decrease in formability caused by the change in the structure of the weld zone and the movement of the weld. Problems such as the inability to accurately locate specific materials: the deformation of the sheet metal on the side with higher strength is small, while the deformation of the sheet metal on the side with lower strength is larger, resulting in uneven deformation on both sides of the weld

If the traditional incremental method simulation software is used, it needs to be called and executed repeatedly in the process optimization design, and the time consumed by optimization often exceeds the acceptable limit, so the optimization loses its meaning

Especially at the beginning of stamping product design, a large number of parameters such as molds and process information are to be determined. If this strategy is adopted, it will consume a lot of manpower and time, and the feasibility is low.

[0004] The reverse simulation algorithm is a blank optimization design method created around the 1990s, but it is used for the prediction of weld seam movement in the laser tailor welded blank forming process and no relevant patent application has been found.

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