Long‐term atmospheric corrosion rates of hot dip galvanised steel and zinc‐aluminium‐magnesium coated steel

Abstract

Zn coated steel (Z) and ZnAlMg coated steel (ZM3.7/3 = Zn–Al (3.7 wt.%)‐Mg (3.0 wt.%)) have been exposed for 6 years at twelve different weathering sites world wide. The mass loss of the coatings have been measured after 1, 2, 4, and 6 years exposure. From the results, it is shown that ZM3.7/3 had always a better corrosion performance compared to Z. The ratio of performance after 6 years of exposure varied from about 1.4 to 4.4 with a mean value of 2.8. At temperate marine sites (e.g., temperature between 9–20°C) with low to moderate SO 2 pollution a good relationship was observed between the relative performance of ZM3.7/3 and the corrosion rate of Z. It was thus concluded that ZM3.7/3 has a better relative performance in harsh environments. The corrosion performance of ZM3.7/3 was shown to be connected to the formation of protective corrosion products.

Novel synthesis of a self-healing Ce based eco-friendly sealing coating to mitigate corrosion in insulators installed in industrial regions

“…The pH of rain varies in the range of 3.2-5.1 in extremely polluted industrial sites of Korea. [3][4][5] Under continuous exposure to an industrial environment, the galvanized lm of the insulator pin would be transformed into other atmospheric products rapidly. These corrosion rates would be faster enough to cover galvanized surfaces with corrosion byproducts in no more than 5-10 years.…”

Electrochemical Corrosion Investigations on Binary and Ternary Zinc Alloy Coatings using Gel Electrolytes

“…In particular, ZnAl, ZnMg, and ZnAlMg coatings are being extensively researched and their corrosion behavior is described. [3][4][5][6][7] Research is also driven by new REACh standards, as a result of which new variants such as ZnW and ZnWCu coatings are being developed. [8] Research is also focusing on other variants such as ZnNi, ZnCo and ZnFe coatings, [9,10] ZnMo coatings, [11] and ZnFeMo coatings.…”

Analysis of metallic coatings based in zinc-aluminium-magnesium alloys, in terms of performance and long-term corrosion. Case study: Electrical cable trays selection in project design

“…In other words, what is being claimed, is that in long term exposure tests, mass loss ratio Z/ZM, is much higher in the firsts years and it tends to 1 over the years and so, the comparative performance of postgalvanized and ZM coatings is distorted in favour of ZM coated steels by focusing on the early years of such tests. This is a relevant matter that has being investigated in the scope of this thesis, taken the opportunity of having 4 years field tests results (Dominique Thierry, Persson, et al, 2019) (Persson et al, 2017)(Dominique Thierry, LeBozec, et al, 2019b and 6 years field tests results (Dominique Thierry, LeBozec, Le Gac, & Persson, 2019a;Dominique Thierry, LeBozec, et al, 2019b This is in order to see which is the corrosion result when removing the effect of year 1 and year 2. For instance, in the case of "Last 2 years" corrosion, this has been calculated, by subtracting the corrosion value of year 2 from the corrosion value of year 4.…”