Spray electrostatic powder Coating of high-density polyethylene on plain carbon steel

摘要

Carbon steel plates were surface treatedmechanically and then chemically before applying High DensityPoly Ethylene (HDPE) coating. Acid etching was performedusing H_2SO_4. In addition a zinc phosphate layer was appliedon a number of specimens. Pre-treated specimens were coatedwith HDPE powder, both with and without an especial stabilizer,using spray electrostatic technique.Effects of various variables such as surface roughness, pre-phosphating treatment, addition of stabilizer and the role ofcuring time and temperature were investigated. For this purpose,various parameters such as quality, adhesion, ductility, corrosionresistance and stability of coating on substrates were studied;using mechanical and immersion tests, Scanning ElectronMicroscopy (SEM) and Infrared (IR) spectroscopy. In addition,using SEM, the microstructure of produced coatings as well astheir interfaces were investigated.The results obtained revealed that, high density polyethylenecoating on plain carbon steel can be obtained with excellentperformance, using spray electrostatic technique. This wasbased on adhesion and ductility; corrosion resistance inH_2SO_4, NaOH, Cl_3Fe and aqueous solutions; salt spraytests; as well as SEM examination and IR spectra.