Effect of the Manganese Phosphate Solution with Additive Agent of Tartaric Acid.

In this study, the correlation between morphology and friction of manganese phosphate coating layer with additive agent of tartaric acid by 2, 4, 6 g were investigated. The microstructure and morphology of the coatings were studied by scanning electron microscopy (SEM), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS) and atomic force microscopic (AFM). Potentiodynamic polarization test was carried out in order to evaluate the corrosion protection properties of manganese phosphate coating in 3.5 wt.% NaCl solution. Also, the tribology property of manganese phophate coating was tested by ball-on disk. In the results of EDS analysis, coating layer consists of elements such as Mn, P, Fe, O, and C. XRD showed that (Mn, Fe)5H2(PO4)4·4H2O in manganese phosphate coating layer was formed by the chemical reaction between manganese phosphate and elements in SM45C alloy. The corrosion resistance of manganese phosphate coating with additive agent was superior than the one without additive agent. Also, in the Fe amount in sludge, manganese phosphate coating layer with additive agent was observed to be considerably decreased.