Smooth PPGI for Roofing Sheet

Aluminum-Zinc Coated Color Base Substrate utilizes a steel sheet coated with an aluminum-zinc alloy—comprising 55% aluminum, 43% zinc, and 1.5%–1.6% silicon—as its foundation. Serving as the primary raw material for the subsequent production of color-coated sheets, it constitutes the mainstream substrate for high-end color-coated products, offering a combination of exceptional corrosion resistance and processing performance. Compositional Structure: The industry standard features a 55% aluminum-zinc alloy coating (commonly referred to as "55% Al"). Its typical composition consists of 55% aluminum, 43.5% zinc, and 1.5% silicon; this forms a dense, stable protective alloy layer on the surface of the steel strip through a hot-dip coating process. Performance Advantages: Its corrosion resistance is 2 to 6 times greater than that of ordinary galvanized steel sheets. It uniquely combines the long-term corrosion resistance of aluminum, the electrochemical protective properties of zinc, and the wetting and coating-aid benefits of silicon. Furthermore, its heat resistance, adhesion, and formability all surpass those of traditional galvanized steel and low-aluminum-zinc coatings, and it demonstrates superior performance compared to 25% aluminum-zinc substrates in salt spray tests. Compliant Mass Production:The industry has successfully achieved mass production of 55% aluminum-zinc color base substrates with coating weights reaching up to 200 g/m². These products fully comply with...