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In order to investigate the effect of operational parameters on corrosion resistance of trication zinc phosphate coating on iron steel's substrate in dip system, a series of experiments were done in laboratory.
After salt spray test, a test that indicates the corrosion resistance of a painted film, the following results were obtained: for free acidity, when it was gradually increased, corrosion resistance of coating increased so that in a certain range, it achieved the best resistance; when it was further increased, the corrosion resistance decreased. For total acidity, it was observed again that within a certain range of total acid, the corrosion resistance of coating was high enough and out of this range decreasing of resistance was
observed. As far as the time is concerned, in an
initial range, corrosion resistance increased but after this initial range, no considerable change in resistance observed. For operational temperature, it was observed again that in a certain range of temperature the coating had its best resistance and out of that this resistance decreased. For accelerator's concentration, in its low concentrations the corrosion resistance was more comparing to its high concentrations. And as far as the activator's concentration was concerned, in lower concentrations the coating had higher corrosion resistance than in higher ones.