What are the conditions that affect the deep drawing of deep-drawn metal stamping parts?
With the development of society, metal stamping products are applied to all walks of life, and people have higher and higher requirements for the quality of metal stamping parts. This requires us to understand more stamping expertise. Today we look at the process of stamping and deep drawing. What are the conditions for its deepening? 1. Mold geometric parameters the size of the punch fillet radius rT has a greater impact on the strength of the dangerous section. If rT is too small, the tensile stress of the metal stamping material when bending around the punch will increase, and the thinning of the dangerous section will increase. If rT is too large, the contact area between the end face of the punch and the material will be reduced, and the bearing area for transmitting the drawing force will be reduced. The material will become thinner. At the same time, the suspended part of the sheet will increase, which is easy to produce internal wrinkles (in the drawing concave (Wrinkles within the radius rA of the die fillet). 2. If the radius rA of the concave die fillet is too small, the resistance of the metal stamping parts of the flange part when the material flows into the gap between the convex and concave dies will increase, thereby increasing the tensile stress in the force transmission area of u200bu200bthe cylinder wall, which is not conducive to reducing the limit drawing coefficient. . However, if rA is too large, the effective blanking area will be reduced, and the flange material will easily become unstable and wrinkle. 3. If the gap between the convex and concave dies is too small, the metal stamping parts will be excessively squeezed, and the friction resistance will increase, which is not conducive to reducing the limit drawing coefficient. However, if the gap is too large, the precision of the deep drawing part will be affected. 4. If the blank holder force is too large, it will increase the drawing resistance. However, if the blank holder force is too small, it will not be able to effectively prevent the flange material from wrinkling, which will greatly increase the drawing resistance. Therefore, under the premise of ensuring that the flange material does not wrinkle, try to adjust the blank holder force to the minimum. 5. Friction and lubrication conditions The working surface of the die and the blank holder should be smooth, and be lubricated with lubricant during deep drawing. Under the premise of not affecting the surface quality of the metal stamping parts, the working surface of the punch can be made relatively rough, and no lubricant is used during deep drawing. These are all conducive to reducing the drawing coefficient. 6. The relative thickness of the blank (t/D) × 100 the greater the value of the relative thickness (t/D) × 100 of the blank, the stronger the ability of the flange material to resist instability and wrinkles during deep drawing, so it can be reduced The small blank holder force reduces the friction resistance, which is conducive to reducing the limit drawing coefficient. 7. The number of drawing times. The deformation resistance of the material is increased due to the cold work hardening of the metal stamping parts during drawing, and the wall thickness of the dangerous section is slightly thinned, so the ultimate drawing coefficient of the next drawing should be greater than The previous one was big. 8. The geometric shape of the deep drawing parts different geometric shapes of the metal stamping parts have different characteristics in the process of deep drawing deformation, so the limit drawing coefficient is also different. For example, the ultimate drawing coefficient of the first deep drawing of the flanged deep-drawn part is smaller than the ultimate drawing coefficient of the first deep drawing of the non-flanged deep-drawn part. Article recommendation: The relationship between the drawing, trimming and flanging processes of the covering parts in the stamping parts Previous post: The role of multi-station progressive die in the processing of metal stamping parts