Three-dimensional Surface Stretch Forming Method Based on Multi-point Force Loading Method

Abstract

The invention provides a three-dimensional curve stretch forming method based on a multi-point force loading mode, and belongs to the field of metal plastic machining. The multi-point force loading mode is adopted to control the plate stretch forming process; the stretch forming force is applied to a series of discrete points at two ends of a plate by loading control units arranged on two sides of a mold; and the magnitude and the direction of the stretch forming force applied by each loading point can be independently controlled. The invention provides a method for determining the stretch forming force of each discrete loading point according to molded surfaces of a stretch forming mold, realizes the stretch forming process of three-dimensional curve parts by minimum stretch deformation through real-time control of the stretch forming force in each discrete point, prevents generation of forming defects, obtains the curve parts with large deformations, can improve the mold pasting process of the plate, reduces residual materials in the stretch forming process, and saves the materials.

Description

technical field [0001] The invention belongs to the field of metal plastic processing, and relates to a sheet metal forming method, which is suitable for stretch forming of large three-dimensional curved surface parts. Background technique [0002] Stretch forming is an important processing method for large three-dimensional curved surface parts, and it is widely used in the manufacture of aircraft skins, high-speed train streamlined front skins, etc. The traditional sheet metal stretch forming adopts integral clamps. During the stretching process, the stretching force exerted by the jaws on the sheet has the same magnitude and direction at all points in the transverse direction of the sheet end, resulting in the stretching force distributed along the transverse direction of the sheet. The length cannot be controlled, resulting in uneven deformation, cracking, wrinkling, slip lines, coarse grains and other defects. These problems are especially prominent when forming materia...

AI Technical Summary

Problems solved by technology

[0004] In the traditional stretch forming of sheet metal, the main cause of various forming defects is that the elongation of the sheet material along the lateral direction cannot be effectively controlled. To solve this problem, the present invention will provide a method based on multi-point force loading The three-dimensional surface stretch forming method uses multi-point force loading to control the stretch forming process of the sheet metal. The stretch forming force is applied to a series of discrete points at both ends of the sheet through the loading control unit. The stretching force applied by each loading point The magnitude and direction of the forming force are independently controlled. Through the real-time control of the stretching forming force at each discrete point, the stretching forming process of three-dimensional curved surface parts can be realized with the minimum stretching deformation, so as to avoid forming defects and obtain high quality surface parts

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