Bakır içeren ayrışmaya uğrayan çeliklerde kromun artırılmasının tropikal deniz maruziyetinde pas tabakası evrimini yönlendirmesi

Özet (abstract)

Weathering steels are vulnerable to sustained chloride deposition when their rust layers fail to stabilize. To clarify how a Cr gradient regulates rust formation in Cu-bearing steels, Q235 and four Cr-Cu steels containing 0.5–3.5 wt.% Cr with relatively stable Cu contents were exposed for two years in the tropical marine atmosphere of Wenchang, China. Mass-loss measurements, rust-layer characterization, and electrochemical tests show that Q235 retains a porous, chloride-permeable rust layer. With increasing Cr content, the relative accumulation of α-FeOOH is favored and a more continuous Cr-enriched inner layer develops, while Cu-containing products preferentially enrich near defects. These concurrent spatial changes are associated with improved resistance of the rust layer to chloride ingress. From Q235 to the highest-Cr steel, the corrosion current density decreases from 43 to 16 μA·cm -2 , and the combined rust-layer and charge-transfer resistance increases from 139.0 to 540.3 Ω·cm 2 . These results indicate that increasing Cr content progressively stabilizes the rust layer in Cu-bearing steels during tropical marine exposure, while Cu-containing species remain preferentially associated with defective regions of the rust layer.

Yazarların özeti; kaynağından alınmıştır. npj Materials Degradation, 2026 · DOI ↗