Predicting Springback In Sheet Metal Forming

The springback properties of sheet metals make the design of forming dies extremely difficult.

Predicting springback in sheet metal forming.

A classification framework for identifying correlations between 3d surfaces in the context of sheet metal forming especially asymmetric incremental sheet forming aisf is described. To act as a focus for the work the prediction of springback within the context of sheet metal forming is considered where springback is a form of deformation that occurs in a non uniform manner across a manufactured 3d surface as a result of the application of some sheet metal forming process. In the forming process both sheet metal and plastic are bent to a specific bend angle. Sulaiman khan frans coenen clare dixon subhieh el salhi department of computer science university of liverpool united kingdom fmskhan coenen cldixon salhig liverpool ac uk.

The objective is to predict springback the deformation that results as a consequence of the application of a sheet metal forming processes. Finite element simulation of sheet metal forming is a well established tool which is used in industrial practice to evaluate geometrical defects caused by elastic springback. When the material is then released from the pressure of forming stresses within the bend tension outside the compression inside causes the bend angle to open and the radius to open. Note predicting springback will never perfect a perfect science.

This paper deals with the springback analysis in sheet metal forming using modified ludwik stress strain relation. Springback can be defined as an elastically driven change of shape of the deformed part upon removal of external loads. Using the deformation theory of plasticity formulation of the problem and spring back ratio is derived using modified ludwik stress strain relationship with tresca and von mises yielding criteraia. In this work a coupled explicit to implicit finite element procedure is outlined for predicting springback deformations in sheet metal forming processes.

Classification based 3 d surface analysis. Springback causes geometric changes in the final shape of the part so it is very important particularly if tight tolerances have to be held. Predicting springback in sheet metal forming m.