Our Research

Sheet Metal Forming: Bending Under Tension

The important aspect of this basis test is that the sheet is deforming plastically through the whole thickness while it is sliding on the friction surfaces. The contact pressures can be adjusted by selection of the radius of the friction pins and the conditions closely simulate the particular aspect of the forming process. The device was designed to detect the friction effects at the work piece/punch corner interface. It consists of two cylindrical pins, which represent the punch corner in 2-D drawing test. During the test the pins are not allowed to rotate and the strains in the legs are recorded by extensometer.

 

ABAQUS and Experimental Results

The experiments also demonstrated that the diameter of the pins can exert an influence on the forming operation. Spring back could also be examined using the equipment. The commercial FE code,ABAQUS, predicting many of the experimental observations.

Finite Element Method Simulations
(ABAQUS)

The variation in the experimental axial
load versus ram displacement

 

A comparison of the measured and predicted strain as function of ram displacement shows the very good agreement. The agreement between the variation in the experimental axial load versus ram displacement and the predicted values also plotted for comparison is very favourable.