Capability of thermodynamic calculation in the development of alloys for deposition of corrosion‐protection coatings via thermal spraying

Abstract

AbstractThe capability of thermodynamic calculations for the development of materials for corrosion protection of steels via thermal spraying is illustrated in several practical examples. Although the thermodynamic calculations are usually performed for the equilibrium state, they can yield important information even about fast chemical reactions that are far from the equilibrium conditions. The relevance and reliability of thermodynamic calculations can be improved significantly if their results are complemented by chemical and microstructural analyses. In this contribution, details on the melting and alloying processes in technically relevant nickel‐based alloys were obtained from the combination of the thermodynamic calculations, differential thermal analysis, local chemical analysis using scanning electron microscopy with energy dispersive spectroscopy of characteristic X‐rays and X‐ray diffraction analysis. Furthermore, the results of the thermodynamic calculations performed on nickel‐based alloys clarified the role of individual chemical elements dissolved in the alloys for the corrosion resistance of the alloys and thus they contributed to the improvement of the chemical stability of these alloys during the chemical reaction with gaseous substances containing chlorine.