Forging Preform Design of Brass Pin

• Main Authors: Wun-Sian Huang, 黃文賢
• Other Authors: Chao-Cheng Chang
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/03298657430748698096

碩士 === 國立高雄應用科技大學 === 模具工程系碩士班 === 101 === Contact pins are key components for connectors and have been widely used in consumer electronics and the testing devices for semiconductors. The geometric feature of the contact pin plays an important role in affecting the quality of the connector. However, it is not easy to use a forging process to form the geometric feature without a preforming stage. This study considered the geometric features including head height, diameter and angle of brass (JIS C2600) contact pins, and the diameter of the billet to vary the dimensions of the pins according to the design rules for the upsetting process. The study used a finite element package DEFORM-2D to simulate the forging processes of contact pins. The predicted results reveal possible buckling and flashing conditions. The geometric features which require a preforming stage were also summarized. Based on the results, a preform design for a contact pin was proposed according to the shape transformation from a billet to the product. By simulations and experiments, the forming load, material flow and hardness distribution were analyzed in order to investigate the relationship between the preform and key geometric features as well as the characteristics of the forging process of contact pins. The results show that a complete die filling can be achieved by a one-stage forging to produce the contact pins with the head angles less than 120∘ for the cases having various the head height and diameter. As the head height and diameter increase, the buckling increases and the flash reduces. For the cases with a constant head diameter, the flash increases with the reduction of the angle. Moreover, a die filling can be improved as the preform shape close to the product shape. The simulations show the large strains occur in the area of the head of the pin. The phenomenon is also observed in both the micrographs showing large grain deformation and the results of harness tests in the same area.