Comparison of welding results with stable and unstable resonators

In order to compare welding performance of stable and unstable resonators an industrial axial-flow-CO2-laser in the 5 kW range has been operated with two stable and one unstable resonator at 5 kW. Along with a beam diagnostic analysis of the beam quality benchmark welding tests have been carried out. The results show, that for stable resonators the beam quality is a measure of the welding performance. However the unstable resonator shows considerable higher welding depth as predicted by beam quality dependency found for stable resonators.