New protective coatings with satisfactory performance and low impact are required by the surface treatment industry as effective Cr(VI)-free substitutes. Recently conversion coating systems containing Zr/Ti have shown great promise particularly for zinc finishes on steel and in this paper, we study the influence of bath conditions (e.g. pH and time) on conversion layers composed of a Zr-based film. The coating formation was studied by simultaneous monitoring of open circuit potential and surface pH using a novel cell design. Samples were subsequently characterised by electrochemical impedance spectroscopy in NaCl over a 24-hour period. The system demonstrates a correlation between pH of formation and corrosion resistance.
Commission Regulation (EU). Regulamento (UE) n. ° 301/2014 da Comissão, de 25 de março de 2014, que altera o anexo XVII do Regulamento (CE) n. ° 1907/2006 do Parlamento Europeu e do Conselho relativo ao registo, avaliação, autorização e restrição dos produtos químicos (REACH), no que respeita aos compostos de crómio VI Texto relevante para efeitos do EEE [Internet]. OJ L, 32014R0301 Mar 26, 2014. Available from: http://data.europa.eu/eli/reg/2014/301/oj/por.
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