Z. I. Nekrasov Iron and Steel Institute of the National Academy of Science in the Ukraine (Dnepropetrovsk, Ukraine):

V. A. Lutsenko

Byelorussian Steel Works (BMZ) - Management Company of “Byelorussian Metallurgical Company” Holding, (Zhlobin, Republic of Belarus):

N. I. Anelkin, vem.tu@inbox.ru

Z. I. Nekrasov Iron and Steel Institute of the National Academy of Science in the Ukraine (Dnepropetrovsk, Ukraine):

T. N. Golubenko

Byelorussian Steel Works (BMZ) - Management Company of “Byelorussian Metallurgical Company” Holding, (Zhlobin, Republic of Belarus):

V. I. Shcherbakov

Z. I. Nekrasov Iron and Steel Institute of the National Academy of Science in the Ukraine (Dnepropetrovsk, Ukraine):

O. V. Lutsenko

The influence of temperature and time parameters of heat treatment on structural change and properties of carbon chromium molybdenum steel has been studied. It has been shown that there are considerable areas with grainy morphology of cementite after high temperature tempering in the structure of steel. It assures reduction of steel microhardness by 25 %, and there are no substantial structural changes after medium temperature tempering. The researches on influence of temperature and time parameters of heat treatment on modification of structure and properties of chromium molybdenum steel showed that there are large areas with grainy morphology of cementite in the structure of steel after high temperature tempering, but there are no essential structural changes after medium temperature tempering. It has been found experimentally that 3 hour exposure with high temperature tempering ensures reduction of steel microhardness by 25 % due to formation of 30 % spheroidized pearlite in the structure. To reduce tempering temperature when producing rolled sections from chromium molybdenum steel it is necessary to have mainly bainite structure in the original hot-rolled billet, which is possible when steel is cooled with speed 1.0 – 1.7 ^oС/sec.

1. E. Gudremon. Special steel. Translated from German. 2^nd edition, abridged and revised. Vol. I-ІІ. Мoscow. "Metallurgy". 1966. 1274 p.

2. V. А. Lutsenko, Т. N. Golubenko, М. F. Evsyukov et al. The influence of cooling rate on structure formation and properties of carbon chromium-molybdenum steel. General metallurgy and heat treatment of metals. PDABA. Dnepropetrovsk. 2009. № 3. P. 56-60.