Abstract
The work studies the processes of contact melting between a mixture of refractory metal powders, carbon nanofibers and substrates made of steel plates of different grades, which arise after applying a current pulse to this composition from a contact welding machine. It has been established that in the proposed system, contact melting and sintering of individual components can occur selectively. This allows us to propose the use of such an effect for forming parts in additive technologies. The addition of carbon nanofibers ensures that contact melting occurs with lower energy costs and between certain components with the formation of materials of the desired structure, grain size, physical and mechanical properties. Experimental studies have shown that due to the rational selection of the composition of the charge, substrate materials and parameters of electrical pulses from the contact welding machine, it is possible to ensure selective directional melting of components and the formation of the material of the part with the desired properties. The introduction of refractory metals (Cr, W, Mo, V, etc.) and nanofibers into the composition of the charge allows us to ensure provide the required hardness, chemical resistance and strength of the material. A small content of metals inactive to carbon (Cu, Ag, Au, Ga, In, Ge, Sn, Pb, Bi and Sb) in the charge significantly improves the wetting and solubility in melts of carbon materials.