Study for Improving Part Quality of Embossing Process with Counterforce

The embossing process is a sheet metal forming method used to create embossed features on the side opposite to the applied force. It is commonly employed in the manufacturing of automotive components, electronic parts, and household electrical appliances. However, a key issue encountered in the process is the curvature at the tip of the embossed feature. This curvature can negatively affect the contact area required for assembly with other components. This study investigates the use of counterpunch forces in the direction opposite to material flow during forming, aiming to reduce the curvature at the embossed tip. Finite element method (FEM) simulations revealed that applying sufficient counter forces can effectively reduce the tip curvature. The optimal size of the counter force in this study is 295 Newtons, resulting in a height of the curvature of 0.022 millimeters at the embossed tip. However, increasing the counter forces also results in a higher forming force requirement. In addition, a closed-die configuration was simulated to constrain material flow direction. This method also led to a reduction in tip curvature, although it significantly increased the forming force in the final stage of the process.