Model for the calculation of the volume change on melting of metals

A phenomenological model has been proposed that allows the volume change on melting of metals to be related to the valence, thermodynamic properties, and crystallographic parameters of the solid phase. Basic to the model are ideas that a phonon “analog of the Casimir force” plays a key role in determining the metal melting process.     

The effect of grain boundaries state on the thermal stability of a submicrocrystalline titanium alloy structure

The thermal stability of the structure and the mechanical properties of submicrocrystalline (SMC) titanium alloy Ti-4Al-2V (industrial designation PT3V) are investigated. The alloy was produced by equal-channel angular pressing (ECAP). It is demonstrated that the enhanced thermal stability of the SMC alloy structure is associated with a change in the concentration of aluminum at the grain boundaries during ECAP.

     

Effect of the severe plastic deformation temperature on the diffusion properties of the grain boundaries in ultrafine-grained metals

A model is proposed to explain the effect of the severe plastic deformation (SPD) temperature on the diffusion properties of the grain boundaries in ultrafine-grained (UFG) metals and alloys. It is shown that an increase in the SPD temperature in UFG metals leads to an increase in the activation energy of grainboundary diffusion from (3–5)k _B T _m, which corresponds to the diffusion parameters of nonequilibrium grain boundaries, to (8–10)k _B T _m, which corresponds to the diffusion parameters of equilibrium grain boundaries (k _B is the Boltzmann constant, T _m is the melting temperature). The dependence of the activation energy of grain-boundary diffusion on the SPD temperature is found to be determined by the kinetics of the competing processes of defect accumulation at grain boundaries and the diffusion accommodation of defects.     

Automated system of error correction for universal multirange reference instruments

Translated from Izmeritel'naya Tekhnika, No. 11, pp. 19–20, November, 1989.     

Arenetricarbonylchromium Complexes in Polymerization Transformations by Radical Initiation of Vinyl Polymerization

The article is devoted to the systematization of investigations of arenetricarbonylchromium complexes in radical polymerization transformation at the initiation of vinyl polymerization. The presented data are shown that these compounds are promising and interesting model systems for the study of the phenomenon of the metal atom action on the reactivity of the monomer π-bond. The correlation between the structure of metal-containing monomers and polymerization parameters, as well as the molecular mass properties of the resulting polymers, are discussed.     

Features of Polymerization of Methyl Methacrylate using a Photocatalyst—the Complex Oxide RbTe1.5W0.5O6

Journal of Inorganic and Organometallic Polymers and Materials - Radical polymerization of methyl methacrylate in an aqueous emulsion was carried out using the complex oxide RbTe1.5W0.5O6 as a...     

Variable quadrature ac bridges for comparing capacitance and resistance standards

The structure of a precision quadrature ac bridge, and its calibration and balancing techniques including error correction are considered.Translated from Izmerital'naya Tekhnika, No. 10, pp. 50–53, October, 1995.