[en] Periodical increase of corrosion potentials and nominal standard potentials in transition metal series of the 4th, 5th, and 6th periods of the periodical system was noted in molten mixtures of sodium polyphosphate and tetraborate and potassium tetrafluoborate, as well as in equimolar mixture of sodium and potassium chlorides at 1173K. Nickel, molybdenum and platinum are characterized by high corrosion resistance in molten salts. The similar strength of these metals was noted at 1123 K in atmosphere of argon and titanium tetrachloride mixture. Austenitic steels and alloys, containing mentioned metals as alloying components, were noted for high corrosion resistance in corrosive media

[en] The method of iron boride FeB, Fe₂B preparation in the melt of sodium and potassium chloride salt mixture with sodium tetraborate or metaborate is suggested. When the temperature reaches 1123 K, amorphous boron is introduced into the salt melt and then - iron powder. The yield of crystal FeB constitutes 90-95 %. The method suggested permits to decrease the process temperature as compared with the known one of 1160-1200 deg C, as well as to eliminate the process of grinding and sizing of product and vacuum

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[en] A study was made on destruction of molten sodium polyphosphate by tellurite, meta-, ortho- and tetratellurate of sodium, as well as di- and trioxide of tellurium at 1073-1223 K. Ortho-, di- and triphosphates of sodium, as well as tellurium (4) and tellurium (6) compounds, promoting change of dynamic viscosity of polymeric melt, were revealed in products of component interaction. It was established that sodium polyphosphate interacted most actively with sodium metatellurate

[en] Corrosion rates for Cu in melts of NaPO₃ containing 0-80 mole% NaBO₂, Na₂B₄O₇, or NaB₅O₈ at 800-1000⁰ decreased significantly with increasing concentration of the B compounds. Corrosion decreased in the series NaB₅O₈>Na₂B₄O₇>NaBO₂ at comparable concentrations. Average activation energies for corrosion were NaPO₃-NaBO₂ 8.3, NaPO₃-Na₂B₄O₇ 15.2, and NaPO₃-NaB₅O₈ 17.2 kcal/mole. Anodic polarization curves for Cu were determined at 850⁰ in melts containing 0, 20, and 100 mole % Na₂B₄O₇, and the solubilities of CuO were determined for all melts at 850⁰. Addition of B salts reduced both anodic potentials and oxide solubility

[en] Stationary potentials have been measured at 850 deg C and corrosion rates found gravimetrically for a number of metals and steels in the eutectic NaCl-KCl melt saturated with HCl. Periodic shifts of the stationary potentials towards positive values have been established in the Ti-V-Cr-Fe-Ni, Cu-Zr-Nb-Mo, Ag-Ta-W-Pt systems, with the corrosion rate of metals decreasing in them. The stationary potentials are shown to shift towards positive values in the series: st.08 KP, st.3, Kh17N2, Kh22N6T, Kh13NChG9, 1Kh18N10T, Kh17N13M2T, OKh17N16M3T, Kh23N18, Kh25N16G7, Kh23N28M3D3T, with corrosive resistance in this series increasing

[en] Electrochemical behaviour of aluminium alloys with rare earth metals (Sc, Y, Nd, Ce, P) in polyvanadium acid salt solutions has been studied by the method of anodic polarization curves. It has been ascertained that in the salt series NaVO₃-KVO₃-NH₄VO₃ their depolarizing activity as regards the aluminium-zinc alloys studied, decreases due to increase in vanadate-anions polymerization degree. 10 refs.; 2 figs

[en] Decrease of corrosion resistance in nickel-copper-doped steel-titanium-St45 steel series in molten sodium phosphate is found by gravimetric method at 1073 K in the presence of manganese (2) and magnesium (2) salts. A shift of corrosion potentials to the region of electronegative values is experimentally confirmed in the given series of metals and steels. Titanium and nickel tendency to passivate in molten sodium phosphate is ascertained by taking the anode polarised curves. Such a property is not typical of cooper and St45