Machinery & Energetics

The urgency of conducting studies with the study of the regularities of the formation of dispersion-strengthened structures of monometallic, bimetallic and composite materials is determined by the need to manage the physicochemical and thermophysical processes of forming materials operating under extreme loads and abrasive wear. The purpose of the study is to optimize the composition, structure and technology of production of such promising materials as dispersion-strengthened by nitrogen and vanadium of steel, bimetals and composites to ensure high and stable quality of the products obtained. The processes of formation of structure and properties of dispersion-strengthened structures of monometallic, bimetallic and composite materials are considered, and analytical regularities of processes are established. Complex optimization of the chemical composition, deoxidation and heat treatment regimes of low- and medium-alloyed cast structural steels with nitride-vanadium hardening doped with manganese, silicon and chromium provides an additional increase in strength properties on 200–250 MPa while maintaining the plasticity level, hardenability in 2.5–3,3 times; characteristics of cold resistance in 1.5–3 times, heat resistance in 1.4– 1.8 times, resistance to reversible temper brittleness in 1.3–2.8 times, wear resistance in 1.4–2.3 times, fatigue strength on 30–70%. The improvement of the technology for the production of bimetallic castings has made it possible to increase the wear resistance in 2.5 to 6.0 times, and to increase the useful life of products from them in 6-8 times compared with the high-magnetic steel 110G13L, and the costs of scarce and expensive metals and alloys (copper, nickel, titanium, chromium, manganese) reduced in 1.7–2.0 times. The development and application of new technology for the manufacture of dispersion-hardened composite castings provided wear resistance increasing of composite products in 2.5–2.9 times, while the working life of crushing and grinding equipment with composite castings increases in 3.0–3.6 times for primary and in 3,6– 3.9 times for secondary grinding of materials, in comparison with the highmagnetic steel Gatfield. In the case of clinker grinding, the increasing is from 2.1 to 3.3 times for compared to bimetallic castings.

steel, structure, properties, nitrogen, vanadium, bimetal, base, working layer, transition zone, composite, matrix, reinforcing particles