This invention relates to galvanic aluminum alloy powder-pigments coated with a semi-conducting corrosion inhibiting oxide and the process for preparing said coated powder-pigments in combination with film-forming binders for coating metal substrates to inhibit corrosion. The coated aluminum alloy powder-pigments are electrically active and prevent corrosion of metals which are more cathodic (electropositive) than the aluminum alloy pigments.