Effect of zinc crystals size on galvanized steel deformation and electrochemical behavior

Abstract

Hot-dip galvanized steel sheets with different spangle sizes were deformed by means of rolling and tension. The change of preferential crystallographic orientation and of superficial characteristics due to the deformation was analyzed by means of both X-rays diffraction and optical and scanning electronic microscopy. A correlation between such changes and the involving deformation modes was intended to be done and the spangle size influence on these modes was studied. Coating reactivity change due to the deformation was investigated by means of quasi-steady DC electrochemical tests. The results allow to infer that, in great spangle samples, the main deformation mechanism is twinning whereas in small spangle ones, pyramidal slip systems happen as well. The increase of the reactivity with the deformation is greater in tension than in rolling and it is more important in small than in great spangle samples.

Effect of Hot Dip Galvanized Steel Surface Chemistry and Morphology on Titanium Hexafluoride Pretreatment

“…[34] [35]. About 1% tensile elongation takes place at the end of the zinc coating process [16] [31], causing extensive formation of deformation twinnings.…”

A Review of Recent Developments in Coating Systems for Hot-Dip Galvanized Steel

“…That is to say, the exploration of a suitable chemical composition of steel will be the first step in the control of hot-dip galvanizing process. Second, modification of the alloy composition in zinc bath for a prescribed matrix steel plays an essential role in galvanizing optimization (Fasoyinu and Weinberg, 1990;Pavlidou et al, 2005;Asgari et al, 2007;Pistofidis et al, 2007;Culcasi et al, 2009). Particularly, the melting point, viscosity, and surface tension of zinc bath can be modified by some certain alloying elements, so that the coating thickness, surface gloss, and mechanical strength of HDGS can be tuned for the better.…”

“…An adherent coating is deposited with the addition of Sb through barrier and galvanic protection (Peng et al, 2020). Third, an appropriate temperature and time for hot-dip galvanizing is another key factor to optimize or regulate the as-prepared galvanizing coating to improve the hot-dip galvanizing process (Fasoyinu and Weinberg, 1990;Asgari et al, 2007;Culcasi et al, 2009). Whether the temperature of zinc bath is too high and too low, it will have adverse effects on the coating properties.…”

Influence of Hot-Dip Galvanised Coating Morphology on the Adhesion of Organic Coatings Depending on the Zinc Bath Pb Content and the Postgalvanising Cooling Method

“…Changing the share of the particular additives in the zinc bath influences the crystal orientation of zinc in the coatings, and, in turn, results in differences in the properties of the coatings [20][21][22][23][24][25][26][27]. Anticorrosive properties of zinc coatings are influenced by the alloying additives, as there is a correlation between the alloying additives content and the texture of the zinc coating surface as well as the shape of its dendrites.…”