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Crystal-geometrical features of the structure of cast and normalized steel with 0.62 % of C content were studied using EBSD method. Inheritance link between the formation of pearlitic and ferritic-pearlitic structures with the structure of intercrystalline boundaries in cast and normalized steel were demonstrated. It was found that the austenite of cast and normalized steel undergoes plastic deformation in conformity with the mechanisms of sliding, twinning and grain boundary slippage. 72 % of low-angle (3... 15 ºС) and 28% of high-angle (20...60 ºС) intercrystalline boundaries are formed in cast steel. Normalization of cast steel leads to the formation of 23 % low-angle (5...15 ºС) and 77 % high-angle (20...60 ºС) intercrystalline boundaries. After normalization of steel the number of special boundaries Σ3…Σ13 increases from 1% to 7 % comparing to its cast state. The number of special boundaries is approximating the number of proeutectoid ferrite in cast and normalized steel.

The results of studies confirming the feasibility of using low-carbon steels for the manufacture of hot deformation tools of the metal are given. These steels have high heat resistance under thermal cycling conditions with water rapid cooling. The efficiency of alloying of steel depends on the type of tool and its working conditions. The developed heat treatment significantly increase the tool life of low-carbon alloyed steels under working conditions.