The air plasma arc cutting 5A06 aluminum alloy section also has a layer of remelting layer, the upper part is 21 Nm, the middle part is 48 um, and the lower part is 23uum. There are pores on the remelted layer, and a certain amount of slag is left at the bottom. This is due to the effect of heat input when the air plasma arc cuts aluminum alloy. In addition to N: reacting with Al, oxygen and other gases in the air will also react with it. In addition, because the energy of the air plasma arc is much lower than that of the laser, the molten metal is not easily blown away by the auxiliary gas, so the molten metal solidifies at the bottom to form dross. The air plasma arc cutting aluminum alloy section has more cracks than laser cutting, and some cutting cracks even extend to the base metal along the grain. The reason for microcracks is the same as that of laser cutting. In addition, the remelted layer of air plasma arc cutting is thicker, less dense and brittle, thus forming more cracks. 

Conclusions

(1) For laser cutting and processing of 5A06 aluminum alloy, the power, pulse width, frequency and defocus in the process parameters have a great influence on the kerf width, while the cutting speed and the pressure of the auxiliary gas have little influence. 

(2) Laser cutting and processing of SA06 aluminum alloy, the front of the slit is narrow, straight and smooth, the widest part of the slit is 0.4, the narrowest part is 0.12 mm, the verticality is 0.28 mm, and the back is almost free of oxidation; Bright, smooth upper part, regular corrugation with trailing angle in the lower part, shallow cut marks. 

(3) The heat-affected zone of SA06 aluminum alloy is not obvious after laser cutting. A layer of remelting layer is formed below 1/3 of the cutting section from the upper surface of the plate, and a few pores and cracks are distributed on the remelting layer. 

(4) Air plasma arc cutting processes SA06 aluminum alloy. The widest and narrowest slits are 4 times and 7.5 times that of laser cutting slits, and the verticality value is 2.5 times. There are more cracks and pores in the remelted layer. .