"Nanoobjects microscopy"

Nano-sized particles of cementite in low carbon steel
Sukhomlyn V. I.1 , Ploshenko L. S.2 
1 Department of Condensed State Physics, State Higher Educational Institution. "DnIprovskiy State Technical University", DGTU, st. Dniprostroevska, 2, 51918, Kam'yanske, Ukraine, tel. +38 (050) 453-87-89 E-mail: v_suhomlyn@ukr.net, ORCID ID: 0000-0002-3673-1353
2 LLC with foreign investment "Atol Paint Ukraine", st. Lazo, 2, 51999 Kam’yanske, Ukraine, E-mail: ludmilaplosenko@gmail.com, 
ORCID 0000-0003-4614-5486

The isothermal transformation of austenite of low carbon steel was investigated [1]. At a high cooling rate, the isothermal transformation of austenite begins immediately with the formation of a quasi-eutectoid, practically without isolating the primary ferrite. The microstructure of a quasi-eutectoid is characterized by the size of cementite particles and the distance between them. In the isothermal transformation temperature range of 500...400 °C, with decreasing transformation temperature, there is a decrease in particle size and a decrease in the distance between them in the ferritic matrix. An example of such a structure and the size distribution of cementite particles after austenite decomposition at a temperature of 400 °C is shown in Fig.1.

Figure 1. Microstructure of quasi-eutectoid in low-carbon steel and size distribution of cementite particles after isothermal decomposition of austenite at 400 ° C. (Transmission electron microscopy).

1.	V. I. Sukhomlyn, Interphase nanoparticles of cementite in low-carbon steels // Book of abstracts “Nanotechnology and nanomaterials (NANO-2017), Chernivtci, 23-26 August 2017, Ukraine, р.13