Yasemin Tunckol

Determination of Strain in Incremental Sheet Forming Process

A simplified method to determine the strain distribution during incremental forming of a cone is proposed in this paper. Because of the symmetry of the deformed part, the strain can be derived using the results obtained from a limited number of consecutive tool contours instead of going through the whole process. Comparisons made between the measured and simulated results show that the proposed method can be applied to determine the strain encountered in such kind of incremental forming process where axi-symmetric parts are formed.

Force Analysis for Single Point Incremental Forming

Single point incremental forming is a new forming process for small batch production and rapid prototyping of sheet metal parts. The forces induced during single point incremental forming are unknown process parameters the magnitude of which is of importance for the development of process models. The purpose of the current study is to develop a method for predicting forces for complex part geometries based on the measured forces for parts with uniform wall angles. Firstly, a set of experiments, planned applying techniques for design of experiments, was performed with the aim of establishing a relation between the forces and the main process parameters for uniform angle parts. A regression equation of the forces was then obtained in terms of four parameters: the vertical step size between consecutive contours, the diameter of the tool, the wall angle of the part and the thickness of the sheet metal. In a second step, a technique of assembling the force curves obtained from the regression equation was employed to predict the forces for other shapes with varying wall angles.