Effect of Laser Cutting on the Mechanical and Fatigue Properties of Aircraft Skin Material
H-L. Hou, Y-Q. Zhao, C. Wu and Z-G. Ren
Laser cutting technology is widely used to achieve good quality cutting of metal sheets. This technology, however, has been deemed to be mainly inappropriate for directly cutting aluminium alloys, owing to their low laser energy absorption rate, resulting in poor quality laser cutting. In order to meet the requirements of non-contact cutting of aircraft skin, a CO2 laser cutting method for aluminium alloy material is proposed. Taking 2A12 aluminium alloy for aircraft skin, as an object, standard specimens of aircraft skin materials were processed by three different processing methods: CO2 laser cutting, CO2 laser cutting and grinding, and mechanical milling. Tensile, shear and fatigue lifetime test analyses, as well as topographical analysis, were conducted and the results compared. The results show that the fatigue life of the laser cut specimens was less compared to that of the mechanically milled specimens. The tensile strength and elongation of the specimens subjected to laser cutting was found to decrease while the yield strength increased. It is concluded that laser cutting technology can be effectively employed in the manufacturing of aircraft skin, by improving the laser cutting process and raising the laser cutting quality.
Keywords: CO2 laser, aluminium alloy, 2A12, aircraft skin, laser cutting, mechanical properties, fatigue life, frozen slag