company news about [Why] 304 Outperforms 201 in Bathrooms

Bathrooms’ perpetual dampness creates an ideal environment for “electrochemical corrosion” (water = electrolyte, oxygen = oxidizer).

304 stainless steel: Its balanced 18% Cr + 8% Ni composition (“18-8 stainless”) forms a dense, self-healing passive film. Nickel stabilizes the chromium oxide structure, preventing film breakdown even under prolonged moisture exposure. If scratched, the film rapidly reforms (via chromium re-oxidation), blocking rust.

201 stainless steel: Low nickel (3.5–5.5%) and high manganese (5.5–7.5%) (a cost-cutting substitute for nickel) result in a weaker, unstable passive film. In humid conditions, the film easily cracks, exposing the metal to corrosion—leading to “pitting rust” or widespread discoloration, especially in water-trapping areas (e.g., corners, welds).

Bathroom cleaners (e.g., acidic toilet cleaners, alkaline soaps) and bodily fluids (sweat, which contains salts) aggressively attack metal surfaces.

304 stainless steel: High nickel and low carbon content make it highly resistant to acids and alkalis. For example, dilute hydrochloric acid (found in toilet cleaners) or alkaline soap residues rarely damage its passive film. Its low carbon content (<0.08%) also prevents “intergranular corrosion”—a process where excess carbon forms carbides at grain boundaries, depleting chromium and weakening the film.

201 stainless steel: Higher carbon content (<0.15%) increases the risk of carbide precipitation, creating “chromium-depleted zones” that are vulnerable to chemical attack. Acids or salts quickly penetrate these zones, causing localized rust (e.g., black spots or streaks) that spreads over time.

Bathroom fixtures (towel racks, shelves, drains) require longevity and cleanliness:

304 stainless steel: Its robust corrosion resistance ensures no rust formation over 5–10+ years, even in poorly ventilated bathrooms. The smooth, non-porous surface resists dirt buildup and bacterial growth, making cleaning simple (e.g., wiping with water or mild detergent).

201 stainless steel: Typically rusts within 1–3 years in humid environments. Rust creates porous, uneven surfaces that trap grime and bacteria, compromising hygiene and aesthetics. Frequent replacement is often needed, increasing long-term costs.