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New high-porous corrosion-resistant materials are produced from steel fibers and a base porous material made by pressing and sintering of St.10 steel fibers. The materials obtained by chromizing (4.8-7.1 wt.%) and nickelizing (2.1-2.4 wt.%) a 60-90%-porosity base material have yield strength higher by a factor of 2 to 6 than that of the base material. The materials obtained by electrochemical coating of a base fibrous material with eutectic composite Ni-Ni 3 B and subsequent liquid-phase sintering at 1120°C contain 3.5-14.0 wt.% Ni. The yield strength of these materials at a porosity of 60-90% is higher by a factor of 2 to 3 than that of the base material.Alloy steels have higher strength, fracture toughness, corrosion resistance, and creep resistance than carbon steels. They are also easier to harden since they have much lower critical cooling rate such that these steels can be hardened in milder conditions: for example, oil or even air hardening.This paper is focused on the production of high-porous materials made from alloy steel fibers by saturating carbon steel fibers with conventional alloying elements (chromium and nickel), the determination of the main mechanical properties of these materials, and the analysis of their structure.St.10 steel fibers 40-100 μm in diameter were compacted in steel die molds and sintered in vacuum at 1260°C to make base cylindrical samples 15 mm in diameter and 10 mm in height. Then a part of samples was case-hardened in a solid carburizer (a mixture of activated birch and coking coal) at 900°C for 6 h till carbon reached 0.6 wt.% in fibers, which corresponds to the chemical composition of Steel 60. The samples were hardened in water at about 800°C and tempered in air at 300°C.Two batches of samples -from St.10 and Steel 60 fibers -were made for subsequent chromizing and nickelizing of porous materials. The samples were chromized in a fused-seal cask in a mixture of chromium and alumina powder with addition of alkali metal halogenide to promote the formation of volatile chromium halogenides in heating. Isothermal holding temperature was 1180°C and holding time was 2 h. After the impregnation, chromium reached 4.8 wt.% in fibers of the base samples and 7.1 wt.% in the Steel 60 samples.

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