Qhov ruaj khov, ntom ntom patina (natural xeb txheej) ntawm SPA-C tiv thaiv lub hauv paus hlau los ntawm ntau cov txheej txheem ntxiv:
Lub cev barrier cuam tshuam
Lub patina paub tab yog compact, fine-grained, thiab tsawg porosity. Nws zoo thaiv cov dej noo, oxygen, carbon dioxide, chloride ions, thiab cov pa phem me me los ntawm kev ncav cuag cov hlau nto, txwv tsis pub cov txheej txheem electrochemical corrosion.
Muaj zog adhesion thiab structural stability
Tsis zoo li cov xoob, flaking xeb ntawm cov pa roj carbon zoo tib yam, SPA-C's patina bonds nruj nreem rau hauv substrate. Nws tsis tev, tawg, los yog poob tawm thaum lub sij hawm sab nraum zoov raug, tuav ib tug nruam tiv thaiv txheej.
Alloy element stabilization
Alloying ntsiab xws li Cu, Cr, Ni, thiab P yog enriched nyob rau hauv lub patina. Lawv tsim ruaj khov, insoluble oxides thiab complex tebchaw uas txo cov tshuaj reactivity thiab tiv thaiv ntxiv dissolution ntawm txheej txheej.
Kev tiv thaiv electrochemical corrosion
The dense oxide layer lowers surface conductivity and reduces the potential difference between anodic and cathodic areas. Qhov no ua rau tsis muaj zog tiv thaiv corrosion-cell thiab txo tus nqi corrosion mus rau qib qis heev.
Kev kho tus kheej muaj peev xwm rau kev puas tsuaj me
Yog tias muaj khawb me me lossis kev puas tsuaj hauv zos tshwm sim, cov hlau uas tau tshwm sim tshiab yuav oxidize ib txwm nyob hauv qhov chaw. Cov ntsiab lus alloy tsiv mus rau thaj chaw puas thiab maj mam rov tsim kho cov yeeb yaj kiab tiv thaiv ntom ntom.
ruaj khov thickness thiab lub sij hawm ntev durability
Thaum tag nrho tsim, patina nres thickening thiab tuav ib tug ruaj khov microstructure. Nws tsis ntxiab dej los yog nthuav dav zoo li cov xeb zoo tib yam, yog li nws tsis ua kom muaj kev sib txhuam sab hauv, ua kom muaj kev tiv thaiv ntev.
