What are the measures to control the bending and cracking of bending metal stamping parts?

In the bending process of metal stamping parts, the smaller the bending radius, the greater the tensile stress on the outer layer of the bent part. When the bending radius is small to a certain extent, it is easy to crack on the outside of the bending part and form waste products. This phenomenon is called 'bending cracking'. Under the condition that the sheet material is not damaged, the minimum fillet radius that can be bent into the inner surface of the part is the minimum bending radius rmin, and rmin/t reflects the limit bending deformation of the material. In design and actual production, the minimum relative bending radius (rmin/t) is often used to determine the bending process. Let's take a look at the measures to control the bending and cracking of metal stamping parts. 1. Use materials with good surface quality and no defects. If the blank is defective, it should be cleaned up before bending, otherwise it will crack at the defect when it is bent. 2. For relatively brittle materials, thick materials and materials hardened by cold work, heating and bending can be used, or the method of annealing to increase the shape of the material and then bending. 3. For the bending of thicker materials, if the structure permits, grooves can be made on the inside of the bend fillet first, and then bend. 4. The bending radius of the workpiece is smaller than the minimum bending radius. 5. The bending line is perpendicular to the fiber direction of the material. 6. The burr side of the blank is used as the inner side of the curve. Due to the influence of various very complicated factors, the value of the minimum bending radius is generally determined by test methods. Article recommendation: What is the difference between the bending process of different bending stamping parts? Previous: What are the characteristics of the flanging process in the stamping process?