A PROCESS FOR LASER CUTTING A NON-METALLIC MATERIAL

摘要

A process for cutting a non-metallic material (1), which process comprises the steps of: providing a laser cutting apparatus having a laser (2), a gas nozzle (4) and an outlet orifice (6) in the gas nozzle (4); positioning the outlet orifice (6) at a stand-off distance (15) from a surface (7) of the material (1); flowing gas (5) through the outlet orifice (6) to form a gas stream (47); energizing the laser (2) in order to create a laser beam (3); focusing the laser beam (3) through the outlet orifice (6) to form a beam waist (41) at a focus position (48) at or near the surface (7) of the material (t); the process being characterized by; using the laser (2) to strike a plasma jet (9) in the gas stream (47); and using the laser (2) to heat the plasma jet (9) to cause the temperature of the plasma jet (9) to increase sufficiently to cut the material (1) with akerf (31) that has an upper zone (58) having an average roughness less than 5µm Ra.