Types and structure of heterophase inclusions in steels

Abstract

Purpose. The problem of the influence of heterophase nonmetallic inclusions on the properties of steels is actual. The goal of the work was to study the main types and structures of heterophase nonmetallic inclusions in steels. Methods. Comprehensive methods for the study of heterophase non-metallic inclusions (metallographic, petrographic, X-ray microanalysis methods) were used. Results. It has been established that heterophase inclusions have different structure and phase composition. The features of various combinations of phases in microcomposite inclusions are shown. The main types of hetero-phase inclusions in steels are established. Scientific novelty. The structural features of heterophase inclusions in steels are established. A classification of microcomposite heterophasic inclusions is proposed: inclusions of the first type “high-melting phase surrounding with low-melting cover”; the inclusion of the second type of “phases are beside”; the inclusion of the third type of “eutectics”; Inclusions of the fourth type “dispersed phases in a non-metallic matrix”; inclusions of the fifth type "eutectics inclusion-matrix". Practical significance. The use of the obtained results will make it possible to develop technologies for the production of steels with regulated content and types of heterophase non-metallic inclusions, which will significantly improve their technological, mechanical and operational properties.