Plasma detection and control requirements for CO2 laser cutting

This paper reveals the underlying mechanisms for laser-induced plasma formation in fusion laser cutting of stainless steel and aluminium, by means of experimental observations, analytical calculations and FEA simulations. The camera-based monitoring system which has been developed and used for real-time plasma detection is explained, as well as the results achieved for different material/thickness/geometry combinations. Requirements for real-time plasma suppression control strategies are derived and the effectiveness of such control algorithm are illustrated.