Investigation of the effect of pre-deformation shape on cold forming properties in the product material in fastener production

Abstract

Due to product features such as production quality and high surface quality, cold forging and cold extrusion methods are widely used in the production of fasteners. Extrudability plays a key role during the process and is affected by many process parameters. Die shape characteristics directly affect cold deformation. In particular, deformation hardening is influenced by the shape characteristics. The cold extrusion process also significantly affects mechanical properties. In this study, the effect of die shape characteristics on the extrudability of 20MnB4 (EN 10263-4) low carbon steel was investigated. Additionally, finite element analysis was conducted to optimize extrudability. Radiuses, angular, and radius-angular die shapes were used in the experimental and finite element analysis. The SIMUFACT FORMING software was used for finite element analysis. Both experimental and finite element analysis results showed that die shape significantly affects the extrudability of steels. Extrudability of steels can be optimized with the die shape. The highest homogeneous metal flow was obtained in the sample obtained from the radius-angular die shape. Samples with an angular die shape showed the lowest extrudability feature. Hardness and finite element analysis results were consistent.