Energy conditions of gas laser cutting of thick steel sheets

Results of experimental determination of the energy balance in oxygen laser cutting of sheets 5–16 mm thick by a CO$_2$ laser in the operation regime of high-quality cutting with the minimum possible degree of surface roughness are presented. Oxygen is used as an assisting gas. For sheets 5, 10, and 16 mm thick, the energy power fluxes, which are involved into the energy balance equation, normalized to the unit thickness of the sheet are found to be independent of the latter and to have close values.