State and prospects of high-carbon cast iron and surfacings

High-chromium cast irons are used in the mining, metallurgical, and petrochemical industries. High-chromium cast irons are used for repairing and protecting industrial equipment, increasing its wear resistance and corrosion resistance. A brief review of domestic and foreign research in the field of high-chromium cast iron is performed. It highlights the main industries that use high-chromium cast irons and their applications, as well as the requirements and production methods. The article analyzes manual arc welding, semi-automatic welding, submerged arc welding, gas welding, laser welding, induction welding, and plasma surfacing. The influence of heat treatment, alloying, and high-energy effects on the formation of functional properties has been studied, and the structure and properties of high-chromium cast iron with different chromium contents have been compared. The article notes that different methods are used depending on the requirements for the parts.In the commonly used high-chromium cast iron surfacing, primary chromium carbides Cr7C3, Cr3C2, and a metal matrix are present. The carbides have a plate-like, needle-like, or mesh-like structure. They provide resistance to abrasive wear, reduce impact toughness, and improve ductility. The metal matrix can have various structures, including ledeburite, austenite, martensite, and ferrite. It is noted that in most cases, the ideal structure of the welded coatings should consist of evenly distributed chromium carbides in a viscous martensitic-austenitic matrix. The prospects for creating high-chromium cast iron welds using electron beam surface treatment are outlined.