The Boriding Process for Enhancing the Surface Properties of High-Temperature Metallic Materials

Abstract

High-temperature metallic materials operate in environments with a broad spectrum of mechanical and chemical conditions, originating typical failures such as steam oxidation, hot corrosion, and wear-corrosion; the service life of the metallic component is reduced with severe economic losses. The ever-increasing demands for enhanced component performance require continuous improvements in existing material systems. In this sense, boriding is a promising thermochemical process used to increase the surface properties of metallic materials for high-temperature applications. The resulting boride coating has excellent wear resistance at high temperatures due to its high hardness, thermal, and chemical stability, and adhesion to the substrate material. In addition, the boride coating is resistant to corrosion in acidic, alkaline, and salt media, suitable for use in harsh environments. The mechanical and chemical properties of the boride coating are preserved at high temperatures (up to 1000 °C); the probability of the boride coating cracking or spalling at high temperature is negligible. This chapter reviews the various boriding methods as adopted for the formation of boride coating on high-temperature metallic materials to improve its performance for diverse high-temperature applications. Wear, practical adhesion, oxidation, corrosion, and tribocorrosion properties of borided materials are explained in terms of the boride coating-substrate system behavior. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2024.