ABSTRACT Accelerator-side phosphating solutions are widely used for zinc phosphate conversion coating on carbon steel wire rods to impart good lubrication and corrosion resistance during wire drawing of steel. But on the accelerator side, the use of nitrite and nitrate as accelerator agents has challenges of high process temperature, liberation of nitrous gases and high sludge generation. For these challenges, the iron-side phosphating process is used as one of the solutions where the bath is maintained at a higher iron level and aeration is done to oxidise ferrous iron instead of an accelerator. In the literature, details of different processes and bath composition are available but their effects on the characteristics of zinc phosphate coating deposited on the carbon steel wire rod are not available. In this paper, zinc phosphate coating was deposited on different grades and sizes of wire rods using accelerator-side and iron-side phosphate solutions and their effect on coating weight and other coating characteristics was studied using SEM, EDS and Tafel polarisation experiments.
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