STAINLESS-STEEL AS NEW SUBSTRATE FOR COIL COATING

Increasing needs of very high resistance to cosmetic corrosion, of mor e extended service life and reduced maintenance costs for infrastructu res, civil and industrial buildings open new fields of application for coil coated stainless steel. This paper describes the adhesion and co rrosion properties of new coil coated stainless steel materials produc ed in industrial coil coating lines. The use of an electrochemical tes t (electrochemical impedance spectroscopy) can give detailed informati on on the reactivity of the system and allow the performance of differ ent substrates (AISI 409, 430, 316 and 304) coated with different poly mers (polyvinylidene and polyester) to be compared. The results obtain ed show the interesting properties of this new class of coil coated pr oducts. The materials were tested for a long time (about 200 days) in an aggressive environment (3.5% sodium chloride solution) also in the presence of macrodefects. In particular, VIVINOX 430, 304 and 316 reve aled no reactivity, corrosion or disbonding, thus supporting the expec tancy of very long trouble free exposure also in very aggressive natur al environments. (VIVINOX is the brand name of the AST (Acciali Specia li Terni) line of coil coated stainless steel.)