1. Copper (Cu): Cov ntsiab lus tseem ceeb rau Patina Initiation & Stability
Cov ntsiab lus: Feem ntau 0.20–0.50% hauv SPA-H.
Lub luag haujlwm: Qhov tseem ceeb tshaj plaws alloying caij rau huab cua tsis kam. Copper accelerates qhov pib tsim ntawm patina thiab hloov kho nws cov qauv tshuaj, ua rau nws denser thiab ntau adherent rau steel substrate.
Mechanism: Copper ions migrate mus rau steel nto thaum oxidation, tsim tooj liab - nplua nuj hydroxycarbonate tebchaw uas khi nrog hlau oxides (xeb) los tsim ib tug ruaj khov, tsis yog -flaking patina txheej. Yog tsis muaj tooj liab, SPA-H yuav ua kom xoob, tsis muaj kev tiv thaiv xeb zoo li cov pa roj carbon steel.
2. Chromium (Cr): Txhim kho Patina Ceev & Corrosion Resistance nyob rau hauv hnyav ib puag ncig
Cov ntsiab lus: Feem ntau 0.30–1.25% hauv SPA-H.
Lub luag haujlwm: Txhim kho lub patina qhov ntom ntom thiab tshuaj lom neeg ruaj khov, tshwj xeeb tshaj yog nyob rau hauv cov av ntub, kev lag luam, lossis me me ntug dej hiav txwv ib puag ncig nrog cov pa phem ntau dua lossis ntsev tsuag.
Mechanism: Chromium forms chromium oxides nyob rau hauv lub patina, uas sau micro- pores nyob rau hauv cov hlau oxide txheej thiab txo nws permeability rau dej, oxygen, thiab corrosive ions (xws li, chloride ions los ntawm ntsev tsuag). Qhov no ua rau lub patina muaj kev cuam tshuam zoo dua tiv thaiv corrosion ntxiv.
3. Phosphorus (P): Txhawb nqa Uniform Patina tsim
Cov ntsiab lus: Feem ntau 0.07–0.15% hauv SPA-H (ib theem siab dua li cov pa roj carbon steel).
Lub luag haujlwm: Ua kom cov ntaub ntawv patina uniformly hla cov hlau nto, tiv thaiv patchy los yog tsis sib xws rusting uas tuaj yeem ua rau muaj kev xeb hauv zos.
Mechanism: Phosphorus hloov kho cov hlau qhov chaw chemistry kom nrawm oxidation hauv kev tswj hwm, txawm li cas los xij. Nws kuj tseem txo qis tus nqi ntawm patina flaking, tswj kev ncaj ncees ntawm txheej tiv thaiv lub sijhawm.
4. Me Me Alloying Elements (Ni, Si, Mn): Kev them nyiaj yug Synergistic
Nickel (Ni, ~ 0.20-0.50%): Ntxiv mus txhim kho lub patina lub toughness thiab tsis kam mus rau chloride ions, ua SPA-H ntau haum rau me me ntug dej hiav txwv ib puag ncig.
Silicon (Si, ~ 0.15 ~ 0.50%): Pab tsim cov silica-nplua nuj txheej nyob rau hauv lub patina, ua rau nws hardness thiab tsis kam mus puas los yog lub cev puas tsuaj.
Manganese (Mn, ~ 0.80–1.50%): Txhim kho cov hlau matrix yam tsis muaj kev cuam tshuam patina tsim, sib npaug txhua yam muaj zog thiab corrosion kuj.
5. Carbon (C) & Sulfur (S): Tswj tau zoo tshaj plaws
Cov pa roj carbon (C, Tsawg dua lossis sib npaug rau 0.12%): Khaws qis kom tsis txhob tsim cov tawv tawv, nkig carbides uas tuaj yeem ua rau thaj tsam corrosion thiab txo patina adhesion.
Sulfur (S, Tsawg dua lossis sib npaug rau 0.035%): Minimized los tiv thaiv kev tsim ntawm sulfide inclusions, uas yog nquag mus corrosion thiab tuaj yeem cuam tshuam cov qauv tsim ntawm kev tiv thaiv patina.
