A comparative study of the forming of EN3 mild steel sheets with C0 ₂ and high power diode lasers

A comparative investigation of the effectiveness of a high power diode laser (HPDL) and a CO₂ laser for the forming of thin section EN3 mild steel sheet has been conducted. For both lasers it was found that the induced bending angles increased with an increasing number of irradiations and high laser powers, whilst decreasing as the traverse speed was increased. It was apparent from the experimental results that the laser bending angle was only linearly proportional to the number of irradiations when the latter was small due to local material thickening along the bend edge with a high number of irradiations. Owing to the mild steel's greater beam absorption at the HPDL wavelength, larger bending angles were induced when using the HPDL. However, under certain conditions the performance of the CO₂ laser in terms of induced bending angle was seen to approach that of the HPDL. Nevertheless, similar results between the two lasers were only achieved with increasing irradiations, thus it was concluded that the efficacy of the HPDL was higher than that of the CO₂ laser insofar as it was more efficient.