Cutting of stainless steel with fiber and disk laser

Laser cutting is a major application of laser materials processing. The cutting is usually performed with CO2-laser due to its good beam quality and its relatively low costs of ownership. Ever since entering the market the high power solid state lasers have been expected to achieve a dominating role also in cutting applications. This has not happened mainly due to the fact that beam quality has not been sufficient. The introduction of new generation of solid state lasers has raised the interest of use of them in cutting application. This study was concentrated on use of fiber and disk lasers, the new laser types with a high beam quality, in cutting of austenitic stainless steel. The performance of these new lasers at power level of 4 kW was compared with CO2-laser in respect of cutting speed, kerf width, kerf edge roughness and perpendicularity (squarness) in order to validate the potential of both of the new lasers against traditional CO2-laser. The results showed that the new lasers offer a great potential in improving the productivity of cutting phase with an acceptable edge quality. This is emphasized in thin sheets of 1.3 and 2.3 mm thickness. In that case the width of the cut kerf is considerably narrow especially when using a fiber laser. In case of thicker sections (4.3 and 6.2 mm) the focal length was increased in order to reach an acceptable cut quality still providing a competitive cutting speed in comparison to a CO2-laser. The fiber laser was the fastest cutting laser in case of each thickness. The results were very promising and it can be stated that these new laser types have a great potential in cutting and will probably gain a considerable market share not only in 3D cutting applications but also in ordinary flat sheet cutting