Theoretical and experimental aspects of laser cutting with a direct diode laser

Recent developments in beam coupling techniques have made it possible to scale up the power of diode lasers with a laser beam quality suitable for laser cutting of metal sheets. In this paper a prototype of a Direct Diode Laser (DDL) source (BPP of 22mm-mrad) is analyzed in terms of efficiency and cut performance and compared with two established technologies, CO2 and fiber lasers. An analytical model based on absorption calculations is used to predict the performance of the studied laser source with a good agreement with experimental results. Furthermore results of fusion cutting of stainless steel and aluminium alloys as well as oxygen cutting of structural steel are presented, demonstrating that industrial relevant cutting speeds with high cutting quality can now be achieved with DDL. •A direct diode laser source is used for laser cutting of metal sheets.•Energy efficiency and cut performance are compared with other technologies.•An analytical model based on absorption is used to predict relative cut performances.•Relevant industrial speeds are achieved with acceptable cutting quality.