O’zbekiston respublikasi oliy va o’rta maxsus ta’lim vazirligi termiz davlat universiteti ter

Normalization of steel - the kind of heat treatment of steel, consisting in heating (above the upper critical point), holding and cooling in air in order to give the metal a uniform fine-grained structure to increase its ductility and toughness

Hardening of steel - steel is heated above the temperature of Ac ₃ and Ac ₁ , maintained and the necessary changes in the structure of the steel, after which it quickly cools.

Vakal'yaemost steel (the degree of hardening) - the property of steel, in which as a result of hardening it increases hardness.

Steel softening is the process of incandescence of hardened steel below the Ac temperature of  critical point, after keeping in a certain period of time at a given temperature a slow or rapid cooling

Sorbitol - structural constituent of iron-carbon alloys - eutectoid mixture of ferrite and cementite, dispersed varieties of perlite

Troostite is a structural component of iron-carbon alloys-an eutectoid mixture of ferrite and cementite, a variety of perlite. Austinit is cooled to about 500 ⁰ s and at this temperature, after which a mixture of ferrite and cementite is formed, in katori the hardness is higher than that of sorbitol .