A study of the initial stages of atmospheric corrosion of formed hot dip zinc coated steel

Document identifier: oai:dalea.du.se:2663
Keyword: Engineering and Technology, Materials Engineering, Teknik och teknologier, Materialteknik
Publication year: 1997
Relevant Sustainable Development Goals (SDGs):
SDG 9 Industry, innovation and infrastructure
The SDG label(s) above have been assigned by OSDG.ai

Abstract:

Hot-dip zinc coated steel sheet is extensively used to improve the corrosion protection of steel constructions. When the sheet is formed cracks in the zinc coating develop in strained areas. The zinc coating gives a galvanic protection of the steel in damaged areas of the coating and at cut edges of the sheet. The degree of protection is, however, dependent on factors such as the geometry and the area of the defects, the coating thickness, the presence of corrosive ions in the electrolyte and the wet time. In this work we have studied the initial atmospheric corrosion of zinc coated steel in defects on bended and scribed material. The samples were exposed to a cyclic indoor corrosion test developed by Volvo (Volvo standard 1027). Scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDS) and Auger electron spectroscopy (AES) were used to monitor the initial stages of corrosion and the growth of corrosion products. The corrosion products were identified as predominantly zinc hydroxycarbonate, zinc hydroxychloride and zinc hydroxide. The amount of corrosion products increases with the size of the damaged area, which suggests that the cathodic reduction of oxygen at the steel substrate controls the corrosion rate.

Authors

Per Carlsson

Högskolan Dalarna; Materialvetenskap
Other publications >>

Ulf Bexell

Högskolan Dalarna; Materialvetenskap
Other publications >>

Mikael Olsson

Högskolan Dalarna; Materialvetenskap
Other publications >>

Hans Klang

Other publications >>

Record metadata

Click to view metadata