Anodic degradation of Zn-Ni coatings in moderately alkaline NaCl solution

• Carbon steel samples covered with initially crack-free zinc-nickel coatings were polarized with a small anodic overpotential in moderately alkaline NaCl solution. Along with zinc dissolution, the coatings developed a mud-crack pattern due to tensile stress release, allowing the electrolyte to access the underlying steel surface. Simonkolleite grew on both the zinc-nickel coating and the steel substrate. The resulting current density, that was first strongly anodic, switched to small cathodic values when the coating surface was almost fully covered by a compact simonkolleite layer. 

Subject headings

TEKNIK OCH TEKNOLOGIER  -- Kemiteknik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Chemical Engineering (hsv//eng)

Keyword

Corrosion

Microstructure

Simonkolleite

Zinc-nickel

Binary alloys

Electrolytes

Nickel coatings

Sodium chloride

Zinc alloys

Zinc coatings

Alkalines

Crack free

Mud cracks

NaCl solution

Overpotential

Steel samples

Zinc dissolution

Zn-Ni coatings

Publication and Content Type

ref (subject category)

art (subject category)