{"id":2545,"date":"2021-06-02T01:30:03","date_gmt":"2021-06-02T01:30:03","guid":{"rendered":"https:\/\/pj4iaixa9m.wpdns.site\/?p=2545"},"modified":"2021-08-13T06:10:23","modified_gmt":"2021-08-13T06:10:23","slug":"how-to-control-three-deformations-of-metal-bending-during-punching-process","status":"publish","type":"post","link":"https:\/\/www.harslepress.com\/pt\/how-to-control-three-deformations-of-metal-bending-during-punching-process\/","title":{"rendered":"Como controlar tr\u00eas deforma\u00e7\u00f5es de flex\u00e3o de metal durante o processo de puncionamento"},"content":{"rendered":"

<\/span>Tempo estimado de leitura: <\/span>14<\/span> minutos<\/span><\/p>\n\n\n\n

The process and characteristics of bending deformation<\/strong><\/h2>\n\n\n\n

Bending deformation process<\/strong><\/h3>\n\n\n\n

In this chapter, V-shaped bending is taken as an example to illustrate the bending deformation process, as shown in Fig. 1-1. At the beginning of bending, the inner bending radius of the blank is greater than the radius of the punch fillet. As the punch is pressed down, the straight edge of the blank is gradually closer to the V-shaped surface of the die, and the radius inside the bending is gradually reduced, i.e<\/p>\n\n\n\n

r0<\/sub>\uff1er1<\/sub>\uff1er2<\/sub>\uff1er<\/p>\n\n\n\n

At the same time, the bending moment arm is gradually reduced, i.e<\/p>\n\n\n\n

\"Fig.
(a) Bending die                    (b) Bending process photograph
Fig. 1-1 Bending deformation process<\/figcaption><\/figure><\/div>\n\n\n\n
\"Fig.
(c) Bending process diagram
Fig. 1-1 Bending deformation process<\/figcaption><\/figure><\/div>\n\n\n\n

eu0<\/sub>\uff1el1<\/sub>\uff1el2<\/sub>\uff1elk<\/sub><\/p>\n\n\n\n

Quando the punch, the blank, and the die<\/a> are completely pressed together, the bending radius and the bending arm inside the blank reach the minimum, and the bending process ends.<\/p>\n\n\n\n

Bending is divided into free bending and correction bending<\/a>. Free bending means that when the bending ends, the punch, the die, and the blank are consistent, the punch is no longer pressed down. Correction bending refers to the punch, concave die, and blank three consistent, punch continues to press down, so that the blank has further plastic deformation, so as to correct the bending parts.<\/p>\n\n\n\n

Bending deformation characteristics<\/strong><\/h3>\n\n\n\n

In order to observe the metal flow when the sheet is bent and to analyze the deformation characteristics of the material, a square grid can be set on the side surface of the sheet before bending. The mesh is usually made by mechanical engraving or photographic etching, and then the size and shape changes of the mesh before and after bending are observed and measured using a tool microscope, as shown in Fig. 1-2.<\/p>\n\n\n\n

\"Fig.
Fig. 1-2 Changes of coordinate grid before and after bending<\/figcaption><\/figure><\/div>\n\n\n\n


Before bending, the sidelines of the material are all straight lines, forming a small square lattice of uniform size, and the length of the longitudinal grid line aa=bb. After bending, it can be seen that the bending deformation has the following characteristics by observing the changes of the mesh shape.<\/p>\n\n\n\n

1.<\/strong> The curved fillet part is the main area of bending deformation.<\/strong><\/h4>\n\n\n\n

After bending, the bending part is divided into two parts: the rounded corner and the straight edge. The deformation mainly occurs in the range of the center Angle of bending \u03b1, and there is basically no deformation outside the center Angle.<\/p>\n\n\n\n

2. In the deformation zone, the blank has deformation in the three directions of length, width, and thickness, but the deformation is not uniform.<\/strong><\/h4>\n\n\n\n