Ormocer (ZrO2-PMMA) Films for Stainless Steel Corrosion Protection

The chemical protection of 316 L stainless steel coated with ORMOCER coatings of polymethylmethacrylate (PMMA) and ZrO₂ has been verified. The coatings were dip-coated on the substrates from sols prepared by mixing zirconium propoxide (ZrOC₃H₇)₄, isopropanol (C₃H₇OH), glacial acetic acid (CH₃COOH), polymethylmethacrylate and water under application of ultrasounds. The films were heat treated between 40 and 300°C in air up to 20 h. Their morphology was studied by electron scanning microscopy (SEM). Their anticorrosion behavior was analysed in 0.5M-H₂SO₄ solutions through potentiodynamic polarization curves at room temperature.The influence of the sol preparation, coating composition as well as of the duration and temperature of heat treatments on the corrosion parameters is reported. The films act as geometric blocking layers against the corrosive media and increase the lifetime of the substrate up to a factor 30.