Copper waxay leedahay iska caabin heer sare ah oo daxalka ah ee deegaanka engegan, laakiin waxay u nugul tahay inay samaysato patina -huumi ama baaruud{1}} oo ka kooban bay'ad gaas, taasoo keenta korodhka caabbinta xidhiidhka. Dusha sare ee aluminiumku waxay u nugul yihiin inay sameeyaan filim oksaydh cufan, taas oo beddelkeeda ka hortagi karta daxal kale. Si kastaba ha ahaatee, iska caabinta filimka oksaydhka (qiyaastii 10⁻⁶Ω·cm²) aad ayuu uga sarreeyaa kan substrate-ka naxaasta ah (10⁻⁶Ω·cm²), wuxuuna u baahan yahay in lagu wanaajiyo iyada oo la marinayo daasadda daasadda ah, dhejinta nikkel ama daawaynta oksaydhka anodic.
Marka la eego saamaynta heerkulka korantada korantada, isbarbardhigga heerkulka iska caabbinta naxaasta (0.0043 / darajo) ayaa ka hooseeya kan aluminium (0.0041 / darajo), laakiin iskudarka balaadhinta kulaylka ee aluminium (23.6 × 10⁻⁻ / darajo) waa 1.4 jeer ka naxaas ah (16.5 × 10⁻⁻) Xaaladaha leh isbedbeddelka heerkulka muhiimka ah, balaadhinta kulaylka iyo foosha baararka aluminiumku aad bay u caddahay, taas oo sababi karta inay dabciso goobaha isku xidhka. Tan waxaa lagu yarayn karaa qaab dhismeed (sida kaydinta daldaloolada ballaarinta) ama iyadoo la isticmaalayo isku xirayaasha dabacsan.