What are the changing characteristics of the bending deformation area of u200bu200bstamping parts?

The bending of stamping parts is divided into free bending and corrective bending. Free bending means that when the bending is over, the punch no longer presses down; corrective bending means that after the blank, the punch and the female die are matched, the punch continues to press down to cause further plastic deformation of the blank, thereby performing the bending Correction. 1. Bending deformation characteristics of stamping parts In order to observe the metal flow when the sheet is bent, and facilitate the analysis of the deformation characteristics of the material, a square grid is often made on the side surface of the sheet before bending with mechanical engraving or photographic etching, and then observed with tools The changes in the size and shape of the grid before and after bending were measured. After bending and deformation, the following characteristics were found: 1. The main deformation area. The bending rounded part is the main deformation zone of bending deformation. After bending, the bending stamping part is divided into two parts: rounded corners and straight edges. The grid of the rounded corners changes from a square grid before bending to a fan-shaped after bending, which is the main deformation area; the straight edges near the rounded corners have a small amount of change; the straight edges far away from the rounded corners are basically unchanged. Through bending at different angles, it is found that the smaller the radius of the bend fillet, the greater the deformation of the mesh in the deformation zone. Therefore, the degree of bending deformation can be expressed by the relative bending radius (r/t). 2. The change characteristics of the bending deformation area of u200bu200bthe stamping parts. In the deformation zone, the blank has changed in the three directions of length, width, and thickness, but the changes are not uniform. ① Length direction. The grid changes from a square to a fan shape. The length of the side close to the die (outside) is extended, and the length close to the side of the punch (inside) is shortened, that is, arc bb> line segment bb, arc aa 3). The deformation of the material in the width direction will be limited by adjacent metals, and the cross-sectional shape changes little. Only a small amount of deformation occurs at both ends, and the cross-sectional shape remains basically rectangular. Since the cross section of the deformation zone is distorted when the narrow plate is bent, when the side dimensions of the bent stamping part have certain requirements or the matching requirements with other parts, subsequent auxiliary processes need to be added. Most of the bending in actual production belongs to wide plate bending. Article recommendation: What are the measures to control bending and cracking of bent metal stamping parts? Previous post: What is the difference between the bending process of different bending stamping parts?