" Nanoobjects microscopy"

Scanning electron microscopy in the study 
of nano-sized carbides in cast iron

Sukhomlyn V. I.1, Ploshenko L. S.2 (master student).
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 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: ludmilaplosenko@gmail.com, ORCID 0000-0003-4614-5486

In [1], the phase and structural structure of economically alloyed cast iron was studied under shock-abrasive wear. It is shown that during shock-abrasive action in cast iron, phase transformations occur with the release of several types of alloyed carbides.
In this work, we studied the morphology and phase composition of carbides in white cast iron with a similar chemical composition. The samples were heated to a temperature of 1050 ° C and cooled at an isothermal temperature of 400 ° C. The figure shows that with such heat treatment two groups of carbides formed in the matrix, differing both in size and in chemical composition.
 Primary eutectoid carbides (MeFe3C) were the first to nucleate and grow due to the diffusion of carbon, iron atoms and alloying elements. These carbides in the figure are larger - 0.2 - 0.4 microns in size. More dispersed carbides formed on VC nuclei, which did not dissolve at heating temperature. Their sizes do not exceed 40 - 80 nm., Which is explained by a reduced diffusion coefficient of alloying elements

1.	Bolshakov V.I., Study of phase-structural transformations in wear-resistant cast iron 200Г5Х2ТЛ during operation / V.I. Bolshakov, S. V. Bobyr, S.I. Veselova, V.I. Sukhomlyn // Collection of scientific papers. Issue 48b part 1, Dnepropetrovsk: PSACEA, 2009, - P.168-173.