Characterization of aluminum anodized layers modified in sulfuric and phosphoric acid baths and their effect on conventional electrolytic coloring

► Modification in phosphoric acid can increase pore diameter of the anodized layer. ► The increase in pore diameter can promote electrolytic interference colors. ► Modification in sulfuric acid highly increases the conductivity of the layer. ► Phosphoric acid modification leads to more inferior mechanical properties. ► Modification in phosphoric acid results in no resistance to thermal stress cracking.