Effect of oxygen in laser cutting process

Laser cutting has become an acceptable process in automated sheet metal industry. Efficiency and quality can be maintained with laser cutting. However, oxygen assisted cutting may influence the metallurgical structure of the cut edges. Consequently, in the present study, oxygen diffusion into solid substrate in the vicinity of the cut edge is considered together with the metallurgical changes at the cut surface. To achieve this, an experiment is designed and conducted to cut stainless steel workpiece with a CO₂ laser beam at different oxygen pressures. To determine the elemental distribution in the vicinity of the cut edges, Micro-Particle Induced x-Ray Emission (μ-PIXE), Nuclear Reaction Analysis (μ-NRA) and EDS are carried out. It is found that no oxygen peak is evident at the cut edge and Cr, Al and Si are enriched locally.