1. Q355NH has excellent inherent weathering corrosion resistance in normal outdoor atmospheres
2. Corrosion resistance performance in different environments
Ideal environments (urban/rural/inland): Achieves the best corrosion resistance; the patina matures in 12–24 months and remains intact, with almost no visible material loss during long-term use.
Mild harsh environments (mild coastal/slight industrial areas): Maintains good anti-corrosion effect; the patina densifies further to resist mild salt spray/industrial dust, with only a slight increase in corrosion rate (still ≤0.05 mm/year).
Severe corrosive environments (high-salt coastal/heavy industrial/acid mist zones): Corrosion resistance is reduced (cannot form a stable patina quickly); localized pitting or accelerated oxidation may occur, and additional protection (transparent sealer, anti-corrosion primer) is required.
3. Key advantages over ordinary carbon steel in corrosion resistance
Ordinary carbon steel forms loose, flaky rust that cannot block water/oxygen penetration, leading to continuous internal corrosion and rapid material loss.
Q355NH's alloy-modified patina is dense, non-flaking and self-healing: minor surface damage triggers rapid re-oxidation of the exposed steel, with alloy elements migrating to form new patina and repair the protective barrier, ensuring long-term corrosion resistance.
4. Corrosion resistance consistency with processed Q355NH plates
