The microstructure, tribological and physicomechanical properties of hot-forged composites based on stainless steel of the austenitic class with additions of carbon, Cr 3 C 2 and MoS 2 are studied. The possibility is established of using these composites for powder structural articles resistant to wear and corrosion.Information about the preparation of dense wear-resistant materials based on stainless steels is very limited and it mainly concerns steels of the martensitic class, for whose preparation powder alloys of the corresponding composition or a mixture of iron powder with chromium-and carbon-containing components are used. As these components it is possible to use fine powders of chromium or chromium carbide and graphite [1,2]. Materials have also been studied [3-5] based on stainless steels of the austenitic class whose wear resistance is created by introducing solid additions to the charge (predominantly carbide additions) or by simultaneous use of carbide-forming elements and graphite. Typical for these materials is use during their preparation of fine (not more than 3-5 μm) additions of carbides or carbide-forming elements, and also of the method of single-stage compaction and sintering.We have prepared by single-stage compaction and sintering [6] composites resistant to wear and corrosion based on stainless steels of the austenitic class also containing inclusions of chromium carbide that markedly increase their wear resistance compared with known materials. In addition, apart from chromium carbide, within the composition of these materials there was some percentage of molybdenum disulfide that improves their tribological characteristics, in particular it reduces the friction coefficient especially in the absence of a lubricant.A disadvantage of the materials developed is their relatively low physicomechanical properties caused by porosity. In addition, porosity makes heat treatment difficult that is necessary in order to improve the physicomechanical and tribological properties of materials. In view of this a study was made of the possibility of preparing wear-resistant composites based on stainless steels by hot forging of porous billets. Thus, the aim of this research is to study structure formation during hot forging and heat treatment of wear-and corrosion-resistant materials based on stainless steel of the austenitic class grade Kh18N15 with different additions, and also to study the physicomechanical and tribological properties of composites.Composites based on steel Kh18N15 were studied with additions of 15% chromium carbide, 5% molybdenum disulfide, and 0.6% carbon, and also with additions of carbon alone (up to 1.4%). The standard was steel of the same grade without additions. Choice of objects was based on the results of work in [6][7][8].

The structure and mechanical and tribotechnical properties of iron-boron-carbon alloys produced from a mixture of iron, boron carbide, and graphite powders by single pressing and sintering are used to examine heterophase wear-resistant materials containing from 0.8 to 2.4% boron and from 0.7 to 1.6% fixed carbon. The wear resistance of the materials depends on the ratios of boron and carbon in them and on their total content and substantially exceeds the wear resistance of ShKh15 steel chosen as a reference sample.Iron-carbon alloys are most commonly used structural powder materials since their production is relatively simple and the initial components are readily available [1,2]. To improve basic mechanical and operational properties of these alloys, they must be additionally doped.Boron carbide is a compound that has proved to be highly effective in doping sintered structural iron-based materials (especially in the manufacture of parts subjected to wear during operation) [3-9] and wear-resistant coatings [10][11][12][13][14].We have analyzed papers that focus on the production and properties of boron-containing powder materials for different purposes (including wear-resistant ones) that are made of iron powder mixtures with different contents of boron carbide and revealed that the structure and properties of these materials can be controlled not only through variation in their B 4 C content [7] but also through additional introduction of carbon into the initial charge [8], which leads to significant hardening of Fe-B 4 C materials.There have been no systematic studies of the tribological properties and structure of these materials. The only exception is the paper [5] that provides the wear characteristics of Fe + 3% B 4 C material; however, it is difficult to assess them appropriately as the paper includes no data on experimental conditions, in particular, loading and the counterface rotation speed and time.

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