Investigation of the cold forging operation steps’ effect on forming behavior

Abstract

Cold forming is a manufacturing process that plastically deforms metal using dies. It allows for high speed production, little to no material waste compared to conventional machining, and creates a stronger end product due to work hardening of the material. Cold working in forging process refers to the process of strengthening steel alloy by changing its shape without the use of heat. Subjecting the alloy to this mechanical stress causes a permanent change to the metal's crystalline structure, causing an increase in strength. At this time applied deformation rate, velocity and die design of product effect the mechanical features, flow-orientation properties of sample and load requirements for forging process of rivets. In this study, it is aimed to investigate the operation steps effect on formability characteristics of rivet produced by cold forming with the support of finite element method. Effective plastic strain, yield stress and forging force variations depending on die design were obtained by simufact.forming simulation software. Simulations made with different die designs and physical production results of these dies were compared. The effects of the number of forming operations and die cavity on the process were determined by performing material flow, hardness and structural analysis.

Keywords

• Cold Forming
• Finite Element Analysis Method
• Plastic Forming
• Rivet

References

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