Higher durability is increasingly required for construction materials in order to conserve resources and reduce maintenance work. Since 55%Al-Zn alloy coated steel sheets exhibit excellent corrosion resistance, their use in construction for roofing and siding is expanding. NKK has developed and marketed a high-quality, thin organic com-posite coated 55%Al-Zn alloy coated steel sheet, "SUPER GENIUS", and a prepainted steel sheet, "GALFLEX-COLOR" for these applications. This paper outlines the development processes and main properties of these two new products.

55%Al-Zn alloy coated steel sheets, Organic composite steel sheet, Prepainted steel sheet, Construction, Forming, Roofing, Siding