Optimizations of electric current assisted chemical milling condition of 2219 aluminum alloy.

The chemical milling condition of 2219 aluminum alloy is investigated in the NaOH + Na 2 S + triethanolamine + Al 3+ alkaline system by the assistance of electric currents. The purpose is to study the influences of electric current densities on both the milling rate and the surface roughness of 2219 alloy under different temperatures, NaOH concentrations and additions of inhibitors. The experiments are carried out under the given requirement that the milling rate is from 0.08 mm/min to 0.14 mm/min and the surface roughness is less than 0.65 μm. The reaction temperature of the chemical milling process can be reduced by 10 °C with the application of current densities in the range of 0–20 mA/cm 2 . The concentration of NaOH in the alkaline system can be reduced from 180 g/L to 120 g/L with the application of current densities in the range of 0–60 mA/cm 2 . With the addition of Na 2 SiO 3 , Na 2 CO 3 and Na 2 SnO 3 inhibitors in the alkaline system, both the milling rate and the surface roughness of 2219 alloy decrease. The region enclosed with the suitable NaOH concentration and current density expands and moves towards the high current density. [ABSTRACT FROM AUTHOR]