Effect of Air Resistance in Electromagnetic Forming of Thin Sheet Based on S-ALE Method

The effect of air resistance on thin-walled sheets cannot be ignored during electromagnetic forming (EMF). More importantly, the magnitude of air resistance and the distribution of the flow field are difficult to obtain through experimental measurement. To address this issue, a multi-physics field simulation model using structured Arbitrary Lagrange Euler (S-ALE) method is constructed. The results show that air resistance decreases significantly with decreasing ambient air pressure. As the width of the workpiece increases, the attenuation of the air resistance grows. The parameter benefit ratio is defined to evaluate the advantage of generating low air pressure. The benefit ratio is highest at an ambient air pressure of 60 kPa and decreases significantly below 20 kPa. Moreover, uneven flow field distribution affects the surface topography of the workpiece.