Rezumat
CZU 537.523:53.097:621.763
DOI https://doi.org/10.52577/eom.2021.57.6.50
A series of electrical explosions in propane-butane of single and strand-connected Ti and W conductors with various diameters was carried out. Electrophysical characteristics of the explosion revealed that resistive heating of conductors is characterized by two monotonically ascending sections on the voltage – current curves separated by a flat segment (plateau), which corresponds to relatively stable electrical resistivity of refractory metals in the liquid state. The energy deposited by changing the power input into the conductor during its resistive heating, which can be higher or lower than its sublimation energy and can be regulated by changing the external adjustable parameters of the discharge circuit, is a key indicator determining the structural-phase state of destructed and chemically synthesized products after the explosion. The conditions are achieved under which micro- and nano-sized powder products do not contain residual metals and consist of carbide phases completely (TiC with an average microhardness of 29580 MPa as a result of the titanium explosion and a mixture of W2C+WC1-х, in which stabilized high-temperature non-stoichiometric cubic carbide WC1-x dominates, with an average microhardness of 16770 MPa as a result of tungsten explosion).
Keywords: electrical explosion of a conductor, refractory metals, energy deposition rate, sublimation energy, powder, carbides.