Diode laser bending of tongues from slotted steel tubes

A high power diode laser was used to bend slotted tubes. Two stainless steel tubes, different in diameter but with the same thickness, were cut to generate a rectangular tongue on their cylindrical surface. Subsequently these tongues were formed by diode laser in similar process conditions (laser power, rim speed and focalization condition). Two finite element models were built to predict the laser forming processes for the two different tubes and a good agreement between numerical and experimental results was obtained. Even if the tubes behave in a similar way under laser exposure, a larger deformation of the tongue is present for the biggest tube. Moreover, the deformation history during the laser scan differs. However, in both cases, the single tongue deformed in analogy with a flat sheet metal, despite of the cylindrical surface.