steel SZACC (Galvalume) Steel Sheet: JIS G3321 Explained — 55% Al-Zn Coated Steel for Long-Life Applications
SZACC is Japan's 55% Al-Zn alloy-coated steel sheet under JIS G3321 — the same product as Galvalume or GL steel. Aluminum provides barrier protection; zinc provides galvanic protection at cut edges. 2–4× longer corrosion life than equivalent-weight SGCC. Full guide with AZ coating codes and applications.