Modeling of plasma formation in laser cutting

The formation of plasma plumes in laser cutting prevents the correct absorption of radiation by the base material, thus leading to unsuccessful results of the operation. In order to detect and prevent such conditions, machines can be equipped with plasma sensors, adding costs and complexity to the equipment. An alternative is here proposed, by analytically evaluating the phenomenon of plasma formation within the kerf, once operative conditions of the cut are defined. The analytical model allows, in a process planning environment, fast responses on the plasma global absorption coefficient to be obtained (with respect to a particular laser beam), and can thus be used in order to evaluate the real portion of the beam transferred to the processing material. A priori knowledge of plasma formation can be thus used as a guide for avoiding the formation of plasma and obtaining more reliable process parameters during setup.