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A series of iron alloys for wear applications containing 14 %Cr, 3 %V and 1.5 to 4.2 %C is investigated in as-cast and quenched condition. In almost all alloys carbide phases were hexagonal M7C3 and cubic VC carbides. Critical points of the alloys were determined dilatometrically; cooling from 1000 °C at a rate of 0.4 K/s results in diffusional decomposition of austenite, and at the rate of 15 K/s (air) - in martensitic transformation. The experiments on modifying the alloys with 0.1–0.5 %Ce showed that cerium refines the structure at the concentrations not exceeding 0.3 %Ce. Strength and wear resistance reach maximum at ~ 0.2–0.3 %Ce, and alloy hardness is not significantly affected. Heat treated (quench hardened) alloys show typical behaviour of high-carbon ledeburitic alloys, viz. hardness as a function of quenching temperature reaches maximum when the amount of retained austenite is increased. The greatest hardness of 68.5 HRC is achieved in the 3.5 %C alloy, which also has the highest wear resistance. A method of phase composition and hardness calculation for high-carbon alloys based on thermodynamic description of ternary system Fe–Cr–C is presented; the calculation results align with the experimental data.

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The results were shown in influence of fast heating parameters on the structure and properties of cold-worked alloy AMg6 with original hot-forged structure. Based on the measured data, the change of mechanical properties of cold-worked alloy AMg6 during the process of short duration heating was evaluated. There was reviewed the role of the temperature and the time of heat on the processes of softening the samples of cold-worked alloy AMg6. The stability of mechanical characteristics of hammer-hardened alloy AMg6 under elevated test temperatures was evaluated. It is shown that the return processes in cold-deformed AMg6 alloy during heating in the temperature range studied receive the most intensive development in the first 5–10 minutes, reducing the hardening effect from cold deformation, determined by tensile strength, respectively: by 8–9% with 100 °C; 26–27% at 150 °C; 37–38% at 200 °C; 42–44% at 250 °C and 50% at 300 °C. A decrease in the yield strength during high-speed heating in the temperature range studied is much faster ,compared with the change in the tensile strength. Hour exposure at 200 °C reduces the hardening effect on the yield strength from 340 MPa to 258 MPa, while the tensile strength decreases from 430 MPa to 385 MPa.