As a substitute for the chromate conversion anticorrosive system CRM has developed a new conversion coating based on silica nanoparticles. This new process will be implemented on galvanizing lines just after the zinc bath where the metal strip is still hot. The strip is dipped into a batch containing a suspension of these nanoparticles. Thanks to the strip heat, the solution is locally destabilized and the nanoparticles precipitate onto the metal. The result is an ultra-thin coating (50-200 nm), very compact, that can provide excellent paint adhesion and anticorrosion properties.