Faraday power is the DC power needed only for the formation of aluminum oxide in anodizing. The total DC power used in DC anodizing at 20°C exceeds the Faraday power more than twice, and in hard coating at 0°C it is about 6 times higher. The total DC power is reduced if AC power of industrial frequency is sent to the process tank along with DC power. The AC power unclogs the pores of the oxide film from accumulated free oxygen. This reduces opposition to DC flow, reducing the DC voltage needed to maintain the required level of DC. The lower DC voltage proportionally reduces DC power, until it drops to nearly Faraday power. The negative effects of excessive DC power on the quality of coatings are demonstrated.
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