Oxidation resistant silane coating for hot-dip galvanized hot stamping steel

A silane coating was developed for hot-dip galvanized (HDG) steel via a sol-gel roll coating method and its oxidation resistance during austenitization was detailed. The HDG steel with silane coating retains metallic appearance after 900 degrees C austenitization for 5 min. Moreover, the silane coating preserves more Zn in the alloy layer, conferring better corrosion resistance. Liquid metal embrittlement is absent when a thinner Zn coating (similar to 7 mu m) is applied, yet imparts cathodic protection to the austenitized silane-coated HDG steel with a cosmetic coating. The silane coating markedly inhibits oxidation and confers enhanced corrosion resistance for hotstamped HDG steel parts.