Method and apparatus for producing zinc-aluminum alloy-coated steel sheet with superior workability and corrosion resistance

• Main Authors: SONG, YOUNG-KEUN, MOON, BYUNG-SUN, KWON, CHEOL-HO, LIM, BYUNG-MOON, JUNG, SU-HWAN
• Format: Patent
• Language: English
• Published: 07.05.2015
• Subjects: CHEMICAL SURFACE TREATMENT; CHEMISTRY; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATIONOR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY IONIMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING MATERIAL WITH METALLIC MATERIAL; COATING METALLIC MATERIAL; DIFFUSION TREATMENT OF METALLIC MATERIAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; METALLURGY; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THESURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION

Disclosed is a method for producing a zinc-aluminum-based alloy-coated steel sheet with superior workability and corrosion resistance by coating a base zinc aluminum-based alloy-coated steel sheet in a coating bath comprising 35 to 55% by 5 weight of zinc, 0.5 to 3% by weight of silicon, 0.005 to 1.0% by weight of chromium, 0.01 to 3.0% by weight of magnesium, 0.001 to 0.10% by weight of titanium, and the balance of aluminum and inevitable impurities. With the method, it is possible to produce a zinc-aluminum-based alloy-coated steel sheet which exhibits superior workability through control of an intermetallic 3 compound layer (Zn-Al-Si-Cr) and formation of AlCr 2 due to Cr component present in the coating layer, reduces detachment of the coating layer and cracks of coating occurring during molding, exhibits superior corrosion resistance even after processing and has considerably superior corrosion resistance due to Mg2Si alloy phase and inhibition of oxide film formation.