Needle‐shaped anticorrosion pigments based on the ferrites of zinc, calcium and magnesium

Abstract

Purpose

This paper seeks to synthesize needle‐shaped anticorrosion pigments based on the ferrites of Zn, Ca and Mg for metal protecting paints.

Design/methodology/approach

Anticorrosion pigments were synthesized from oxides or carbonates at hot temperatures. The following pigments were synthesized: ZnFe₂O₄, MgFe₂O₄, CaFe₂O₄, Mg_0.2Zn_0.8Fe₂O₄, and Ca_0.2Zn_0.8Fe₂O₄. The prepared pigments were characterized by means of X‐ray diffraction analysis, by measuring the distribution of particle size and by means of scanning electron microscopy. The synthesized anticorrosion pigments were used to formulate epoxy coatings with PVC = 10 per cent for the synthesized pigment and with the PVC/CPVC ratio = 0.3. The coatings were tested for physical‐mechanical properties and in corrosion atmospheres. The corrosion test results were compared with aluminium zinc phosphomolybdate.

Findings

The needle‐shaped particles were identified in the formulated pigments. It was found that all of the synthesized pigments had high anticorrosion efficiency comparable with that of Zn‐Al phosphomolybdate. The needle‐shaped particles markedly contributed to the advancement of the physical‐mechanical properties of epoxy coatings.

Practical implications

The synthesized pigments can be conveniently used in coatings protecting metal bases against corrosion.

Originality/value

The application of the synthesized pigments with the needle‐shaped particles in anticorrosion paints protecting metals presents a new method. The benefit of the application and method of synthesizing anticorrosion pigments is that they do not contain heavy metals and are acceptable for the environment.

Citation

Kalendová, A. and Veselý, D. (2007), "Needle‐shaped anticorrosion pigments based on the ferrites of zinc, calcium and magnesium", Anti-Corrosion Methods and Materials, Vol. 54 No. 1, pp. 3-15. https://doi.org/10.1108/00035590710717339