SELECTION OF MATERIALS FOR LOCALIZED PRODUCTION OF TILLAGE MACHINE WORKING ELEMENTS

Abstract

The article presents a materials-science justification for selecting optimal steel grades for the localized production of working elements of tillage machinery in the Republic of Kazakhstan. The study is aimed at reducing the dependence of agricultural machinery manufacturing on imported supplies and at increasing the service life of components operating under conditions of intensive abrasive–impact wear. A comprehensive comparative analysis of steels 30MnB5 and 65G was carried out, including an evaluation of their chemical composition, microstructural characteristics, microhardness profiles, and performance under real-life field operating conditions. It was established that the boron-alloyed steel 30MnB5 forms a more homogeneous fine-lath martensitic structure and is characterized by a greater depth of the hardened layer, which ensures uniform wear behavior and improved cutting-edge stability when processing abrasive soils. Steel 65G, despite its high surface hardness, demonstrates a tendency to chipping due to a sharp decrease in hardness in the subsurface layers. An economic assessment using the total cost of ownership (TCO) method showed that the use of 30MnB5 steel reduces operating costs by 18–22% and increases the maintenance-free service life by 35–45%. The obtained results can be applied in the development of technological routes and the formation of production lines under conditions of localization of agricultural machinery manufacturing in Kazakhstan.