Azerbaijan Technical University (Baku, Azerbaijan)
S. N. Suleymanova, Cand. Eng., Associate Prof., seyyade.suleymanova@aztu.edu.az
I. G. Gamdullayeva, Cand. Eng., Associate Prof., ilhame.hemdullayeva@aztu.edu.az
A. J. Mansimov, Cand. Eng., Associate Prof., akif.mensimov@aztu.edu.az
B. B. Musurzayeva, Senior Lecturer, beture.musurzayeva@aztu.edu.az

The article discusses modern methods of step-by-step hardening of high-alloy steels used to improve the mechanical and operational properties of tools and parts operating under high loads and wear conditions. The influence of the quenching temperature schedule, holding time and cooling rate on the mechanical properties of steel is analysed. Particular attention is paid to two-stage heat treatment modes, which allow optimising the distribution of carbides, reducing internal stresses and increasing the hardness of the material without significantly reducing its toughness. Based on the analysis of experimental data, it is shown that step-by-step quenching ensures more uniform martensite formation and prevents cracking during the cooling of thick workpieces. The results obtained can be used in the development of technological processes for the heat treatment of stamping and cutting tools, as well as machine parts operated in aggressive conditions.

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