Preparation of phytic acid conversion coating and corrosion protection performances for steel in chlorinated simulated concrete pore solution

摘要

Phytic acid conversion coating (PACC) for steel was developed by a treatment in a Zn2+ doped phytic acid (PAZn) solution at 20 degrees C to improve its corrosion resistance in concrete environment. Thickness, morphology, composition and corrosion protection performances of the PACC were investigated via SEM, XRD, FTIR, XPS and Electrochemical measurements. Corrosion rate was decreased by about 50%-80% for the steel with PACC. Zn2+ could promote the adsorption reaction of PA to form thicker PACC layers on steel surface. A composite structure could form by the combination of PACC and passivation products to restrain chloride attack in alkaline environment.