Influence of assist gas nature on the surfaces obtained by laser cutting of Al-Cu alloys

This paper focuses on the influence of assist gas nature on the surface finishing and chemistry of cut edges obtained during CO2-laser cutting of an aluminium-copper alloy by means of a non-conventional cutting head. Argon, oxygen, nitrogen and compressed air were studied as assist gases. Surface characterization was accomplished by means of X-Ray diffraction (XRD) and X-Ray photoelectron spectroscopy (XPS) analyses of cut edges, showing the formation of oxides and nitrides. Argon was revealed as the more efficient assist gas to obtain best quality results. This makes argon the gas of choice when laser cutting Al-Cu alloys, excluding its higher cost.