www.seipub.org/fwr Friction and Wear Research Volume 2, 2014 22 Contact Characteristics of Metallic Materials in Conditions of Heavy Loading by Friction or by Electric Current Marina I.Aleutdinova *1, 2 , Viktor V. Fadin 1 , Aleksandr V. Kolubaev 1, 3 , Valery A. Aleutdinova 4 1 Institute of Strength Physics and Materials Science of Siberian Branch Russian Academy of Sciences, 2 Seversk Technological Institute - branch of State Autonomous Educational Institution of Higher Professional Education «National Research Nuclear University «MEPhl» 3 National Research Tomsk Polytechnic University 4 National Research University Saint Petersburg State Polytechnical University 2/4 pr. Akademicheskii, Tomsk, 634021, Russia *1 aleut@ispms.ru Received 5 September 2013; Accepted 23 October 2013; Published 15 May 2014 © 2014 Science and Engineering Publishing Company Abstract Friction of composites having composition TiC+metal was realized at pressure more 100 MPa in lubricant medium. Sliding electric contact of metal materials was carried out at contact current density higher 100 A/cm 2 without lubricant. It was shown that these loading parameters cause a friction surface wear which increases at increasing alloying atoms quantity or number of phases in the initial structure of material. Keywords Composite; Initial Composite Structure; Wear; Contact Conductance Introduction Contact interaction occurs mostly in contact spots. Microvolumes of contact spots undergo large plastic deformation and transit to other structural state. Processes (plastic deformation, formation of chemical compounds, etc) in contact zone could percolate into depth more than 20 microns below the surface . As a result, a layer of friction induced structures is being formed and these structures define basic contact characteristics – wear resistance and friction coefficient. High wear resistance occurs when contact layer structure becomes stable in friction process (Fedorchenko, 1980). Therefore it is necessary to exclude, in the first turn, the plastic deformation in contact spots. It is often being achieved by raising the material's yield point, or to be more specific, by increasing the hardness of the initial material structure. As a rule, hardnening leads to decreasing the ductility. Therefore this way may be effective in the absence of structural changes in contact layer during the process of friction. Materials oriented for friction under high pressure must have high structural strength and high hardness of initial structure. Composites based on the titanium carbide could be used as such materials. It is of scientific interest to produce these materials by selfpropagating hightemperature synthesis (SHS), for example, by pressing exothermic powder mixture in combustion wave (Merzhanov, 1995) and then define their performance in friction under pressure above 20 MPa. In addition, it could be interesting to study resources of materials under higher heat flow through contact spots, which might be realized by transmitting electric current through the worn surface. Sintered composites produced by methods of powder metallurgy are used in such friction conditions. Commercial composites can realize satisfactory wear resistance at contact current density lower than 60 A/cm 2 during sliding current collection (Braunovic, 2007). Friction at pressure higher 20 MPa or sliding at contact current density above 60 A/cm 2 may be assumed to be the heavy work conditions. Initial structure of friction pair materials is one of main