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The influence of various schemes of pressure treatment (pressing, rolling) and modes of heat treatment of powder mixtures on the service properties and adhesion strength of the working and current-carrying layers of electrical contacts with a conductivity of at least 75 % of the copper conductivity was investigated. The dependence of the permissible fraction of the working layer in the total contact thickness on its resistivity has been established. It was calculated that the thickness of the working layer of the created electro-contacts of two compositions : 97 % Cu + 1 % C A + 2 % PS (1) and 97.5 % Cu + 1 % C A + 0.5 % PS + 1 % Al2O3 (2), where CA — is activated carbon, PS — (Fe – Cu) nanocrystalline pseudo-alloy with electrical resistance of 3.20 and 3.28 μOhm·cm, respectively, can be increased to the thickness of the copper layer. The composition of the anti-deformation band for the copper layer of contacts — stainless steel is substantiated and selected, the dimensions of the band are calculated. In all cases of pressure treatment, sintering of samples in hydrogen were carried out twice: the first stage (reduction) — after compaction to a porosity of ~ 20 %, the second stage — after final pressure treatment. For sintered materials, the density, hardness, electrical resistance and its maximum spread over the cross section of cylindrical specimens, as well as the strength of adhesion of the working and base layers, were determined. According to the characteristics of the properties of contact materials and manufacturability of their creation, the advantage of the method of their preparation was evaluated. Optimal of the considered processes for producing contacts, comprising a joint rolling with a reduction of 50 % of copper powder and the powder mixture for the working layer (when using the metering hoppers separated for the charge of each layer), sintering at 600 °C, 1 hour, re-compacting rolling with strain 85 % and sintering at 800 °С for 1 hour. This method was used to obtain samples of contacts, which, depending on the composition of the working layer, have a relative density of 0.99 and 0.98, hardness HB 990 and 830 MPa, electrical resistance 2.57 and 2.61 μOhm·cm and adhesion strength of layers > 200 MPa (breaking stress for copper).

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By pressing, rolling and sintering, a composite material (CM) based on copper powder clad with Fe-Cu pseudo-alloy (PA) was created for the working layer of two-layer ruptured electrical contacts. Powder of activated carbon (CA) with a surface of 1000 m2/g served as the arc suppression component. Highly dispersed powders of Al2O3, Fe2Al5, and Fe were also used as additional components. Experimental linear dependences of the conductivity and hardness of copper-based composites on the concentration of individual functional additives have been established. With the addition of mixtures of additional components, CMs were obtained for the working layer of the contact with the following characteristics: electrical resistance — 3.2 – 4.5 μOhm·cm, hardness HB — 790 – 1030 MPa. For a given conductivity of a two-layer contact, which is ≥ 75 % of the conductivity of copper, the dependence of the maximum allowable resistivity of theworking layer (ρ) on the ratio of its thickness to the thickness of the copper layer is calculated. The optimal chemical composition of the working layer of the contact has been determined — 97 % Cu + 1 %  CA + 2 % PA, providing high hardness 1030 MPa and electrical resistance 3.2 μOhm·cm. These characteristics allow creating an electrical contact with a ratio of the thickness of the working and copper layer equal to 1:1.