Phase transformations in iron-carbon alloys doped with rare earth and transition metals

Abstract

Iron-based alloys began to be used so long ago that today they are classified as classical materials, since these alloys have been studied in depth. The production of various products from steel and cast iron naturally takes the first place in terms of volume, since they have a valuable set of properties: a wide range of plasticity and strength, unique technological properties, which makes it possible to apply all technological operations to them - from simple casting into earth to complex pressure treatment processes. This combination of properties provides, first of all, the composition of iron-based alloys with the main alloying element – carbon. The serious disadvantage of ferrous alloys is their low level of corrosion properties. To eliminate this drawback, both steel and cast iron are alloyed with such metals as chromium, nickel, cobalt, etc. Naturally, this leads to an increase in the mass of finished products and structures. Therefore, the search for alloying elements to improve and optimize the composition of ferrous alloys is relevant today. On the other hand, the industry of Uzbekistan produces a sufficient amount of transition, rare earth metals. Thus, the task is to get added value from the production and processing of these non-ferrous metallurgy products. The analysis of the known literature data on this topic shows that research has been carried out on the use of various transition and rare earth metals for alloying ferrous alloys. However, the available scientific results do not allow to speak about systemic knowledge about the use of rare earth and/or transition metals as effective additives for steels and cast irons. The authors studied phase equilibria, determined the compositions of the phases and the reactions occurring in the systems, constructed phase diagrams, their isothermal sections, determined the structure of iron-based alloys with additions of rare-earth and transition metals with all structural components. The prospect of using the products of nonferrous metallurgy of Uzbekistan for the production of high-quality steels and cast irons is shown.