Uzlov K. Scientific basis of structure, mechanical and operational properties formation due to shearing - diffusion transformation of iron - carbon alloys for railway application.

In the work scientific based system of technological procedures for the operation of purposeful structure formation, mechanical and exploitation properties of irons with nodular graphite and micro alloyed with vanadium high strength wheel - tire steels for the manufacture of wear - resistant, durable and reliable in use of parts of railway rolling stock has been established. Temperature intervals of isothermal austenite transformation in the matrix of nodular graphite irons with different types of bainite formation and specific levels of mechanical and operational properties achievements have been estivated. Duplex structure of austenite in ADI matrix and mechanisms of products fracture depending on bainitic matrix type have been identified. Certain features of phase transformations and regularities of structure formation of wheel - tire microalloyed with vanadium grade "T" steel and thermal kinetic diagram of austenite conversion was built. Parameters of steel grade "T" heat strengthening, which provide acicular morphology of ferrites phase in the products structure, have been set. This conduces to achieve the best combination of hardness, strength and impact toughness. Technological process of the manufacture of wheel - tire products considered as an austempering with bainitic and martensitic transformations temperature positions taking into account. Created at work technological elaborations of manufacturing parts for railway rolling stock with high strength, wear - resistance, durability and reliability in operation have been adopted in industrial production of friction elements made from bainitic nodular graphite irons for freight cars bogies and high strength grade "T" wheel - tire products of new generation. 11 normative specifications have been designed, convinced and implemented in industrial practice.