STRUCTURE AND PROPERTIES OF IRON (CHROMIUM STEEL)– HIGH-CARBON FERROCHROME POWDER COMPOSITES E

E.Karaimchuk,
 
V.Masluk,
 
M.I.Podoprygora,
 
Y.A.SYTNYK
 

I. M. Frantsevich Institute for Problems of Materials Science of the NAS of Ukraine, Omeliana Pritsaka str.,3, Kyiv, 03142, Ukraine
Powder Metallurgy - Kiev: Frantsevich Institute for Problems of Materials Science NASU, 2019, #09/10
http://www.materials.kiev.ua/article/2972

Abstract

The effect of production conditions on the phase composition, structure, and properties of powder materials made of iron and chromium steels (Kh17N2, Kh13M2) containing 35 wt.% ferrochrome (FKh800) was examined. The samples of composition (wt.%) 65Kh17N2–35FKh800, 65Kh13M2–35FKh800, and 65Fe–35FKh800 were produced by single pressing and sintering in the range 1150–1270 ºС in vacuum involving isothermal holding for 30 min. The mixtures were preliminary ground in a ball mill in alcohol for 72 h. The high-carbon FKh800 ferrochrome powder (8.6 wt.% С) was prepared by mechanical grinding of bulk material. The microstructure of the samples was studied using a REM-106І scanning electron microscope. The structure of carbide steels was found to change from two-phase (when iron powder was used) to three-phase (when Kh13M2 and Kh17N2 chromium steel powders were used). The composition of the matrix phase insignificantly influences the density and hardness of the carbide steels but slightly increases the bending strength of the Kh13M2 chromium steel-based material. The materials were tested for abrasive wear resistance by dry shaft–plane friction against a diamond wheel. The mass wear of the carbide steels with Kh13M2 and Kh17N2 matrices was lower by a factor of 2.1–2.4 than that of the iron matrix. Corrosion tests were performed with an accelerated method, in which the sample was periodically immersed into a 20% HNO3 solution. The results show that the samples produced from iron and Kh13M2 and Kh17N2 chromium steels are stable in a nitric acid solution.


CHROMIUM STEEL, HIGH-CARBON FERROCHROME, KOMPOZIT, POWDER MATERIALS, SINTERING