This disclosure relates to compositions for protecting a metallic surface susceptible to corrosion, the composition comprising a first component comprising an aqueous mixture of an acid-phosphate of chemical formula Am(H2PO4)m.nH2O, where A is hydrogen ion, ammonium cation, metal cation, or mixtures thereof where m=1-3, and n=0-6; the first component solution adjusted to a pH of about 2 to about 5, the first component having a particle size distribution between 0.04 to 60 micron; and a second component, configured for combination and at least partial reaction with the first component to provide a phosphate ceramic, the second component comprising an aqueous solution or suspension of an alkaline oxide or alkaline hydroxide represented by B2mOm, B(OH)2m, or mixtures thereof, where B is an element of valency 2m (m=1, 1.5, or 2) the second component solution adjusted to a pH of between 9-14.