Husain Mehdi, Joginder Singh, Rohit Kumar Singh Gautam, B. Nikhil, M. P. Roshindas, Gaurav Kumar
Components operating in extreme conditions within the power generation, marine, and aerospace industries often experience severe surface degradation due to erosion, wear, and corrosion caused by solid particles, silt, cavitation, and slurry. Carbide-based materials are widely used to mitigate such deterioration due to their exceptional chemical stability and hardness. These carbides can be effectively applied as protective coatings on critical components through advanced thermal spray, including HVOF (high-velocity oxy-fuel), and HVAF (high-velocity air fuel) plasma spraying processes. Carbide-based thermal spray coatings primarily consist of chromium carbide (Cr3C2), tungsten carbide (WC), or a blend of both. However, factors such as the carbide composition, the type and proportion of binders, and spray process parameters play a crucial role in determining the overall performance of these coatings. This article critically examines the degradation mechanisms and effectiveness of various carbide-based coatings, focusing on the influence of carbide grain size, binder type, and process parameters under different working conditions. Additionally, post-processing techniques are gaining attention to enhance coating performance further by refining their microstructure. A comprehensive overview of post-treatment methods, including cryogenic treatment, laser processing, and heat treatment, is also presented to highlight their role in improving coating durability and functionality.