Method of coating a metal strip and installation for implementing the method

The process comprises initially coating the metal strip with zinc or zinc alloy, rolling the coated metal strip, and carrying out static treatment for diffusion of the rolled strip in a non-oxidizing atmosphere to obtain a strip of which a top surface comprises an alloy layer formed by diffusion of oxidizable metal or metal alloy. The metal strip is initially coated with zinc or zinc alloy with magnesium or magnesium alloy by hot dip galvanizing process, electroplating process and vacuum deposition process. The initially coated metal strip has a thickness of 0.5-15 mu m. The process comprises initially coating the metal strip with zinc or zinc alloy, rolling the coated metal strip, and carrying out static treatment for diffusion of the rolled strip in a non-oxidizing atmosphere to obtain a strip of which a top surface comprises an alloy layer formed by diffusion of oxidizable metal or metal alloy. The metal strip is initially coated with zinc or zinc alloy with magnesium or magnesium alloy by hot dip galvanizing process, electroplating process and vacuum deposition process. The initially coated metal strip has a thickness of 0.5-15 mu m. A magnesium layer having a thickness of 0.2-5 mu m is deposited on the metal strip by vacuum deposition. An alloy layer of zinc-magnesium (Zn 1 1Mg 2) composition is formed during the static diffusion annealing. The coated metal strip is oxidized on a surface before undergoing the diffusion static treatment. The metal strip is subjected to a thermal diffusion treatment at a temperature of less than 200[deg] C for a period of 4-40 hours. An independent claim is included for an installation for the fabrication of a coated metal strip.