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Isothermal molecular dynamics is used to find the magic numbers corresponding to clusters of fcc transition metals: silver and copper. To that end, we use both our own computer program with a tight-binding potential and well-known LAMMPS software whose standard package is designed to model metal systems by the embedded atom method. Regardless of the choice between two relaxation techniques (lowtemperature relaxation at 1 K and the variant involving a gradual temperature decrease with subsequent relaxation at 1 K), magic number 13 is detected that corresponds to the first term of the Chini series. At the same time, other magic numbers are also found that belong and do not belong to this series.

The generalized Thomson formula Tm = Tm(∞)(1-δ)R for the melting point of small objects Tm has been analyzed from the viewpoint of the thermodynamic theory of similarity, where R is the radius of the particle and Tm(∞) is the melting point of the corresponding large crystal. According to this formula, the parameter δ corresponds to the value of the radius of the Tm(R-1) particle obtained by the linear extrapolation of the dependence to the melting point of the particle equal to 0 K. It has been shown that δ = αδ0, where α is the factor of the asphericity of the particle (shape factor). In turn, the redefined characteristic length δ0 is expressed through the interphase tension σsl at the boundary of the crystal with its own melt, the specific volume of the solid phase vs and the macroscopic value of the heat of fusion λ∞:δ0 = 2σslvs/λ∞. If we go from the reduced radius of the particle R/δ to the redefined reduced radius R/r1 or R/d, where r1 is the radius of the first coordination shell and d ≈r1 is the effective atomic diameter, then the simplex δ/r1 or δ/d will play the role of the characteristic criterion of thermodynamic similarity. At a given value of α, this role will be played by the simplex Estimates of the parameters δ0 and δ0/d have been carried out for ten metals with different lattice types. It has been shown that the values of the characteristic length δ0 are close to 1 nm and that the simplex δ0/d is close to unity. In turn, the calculated values of the parameter δ agree on the order of magnitude with existing experimental data.

The Monte Carlo method has been employed to investigate the hysteresis of the process of melting and crystallization of gold nanoclusters using a many-body Gupta potential. The size dependence of the effective specific total surface energy of gold nanoclusters has been calculated and analyzed based on the Gibbs surface phase method.

Based on thermodynamic perturbation theory, we calculate the surface tension for aluminium nanodrops of various radii. The size dependence obtained with the Schommers potential is compared with the results corresponding to other effective pair potentials. It is stated that the asymptotic value of the surface tension of large nanodrops produced by the Schommers potential is better consistent with the existing experimental data.

A method has been developed for obtaining semifinished products on a continuous caster.The method entails deformation of the still-liquid semifinished product for a period of time equal to 0.05‐0.25 of the time required for complete solidification of the product. The cross-sectional area of the product is increased discretely in one or more stages. T he total increase in cross-sectional area is within the range 2‐100%. The cross-sectional area is increased at least once while the profile of the product is also being changed. The initial cross section of the semifinished product, before its deformation, is either rectangular or is inscribed in a rectangule. The final cross section, after deformation, is circular, square, polyg onal, or rectangular. The semifinished product’s cross-sectional area is increased 2‐35% in each stage. A rectangular or oval cross section is imparted to the semifinished product when its cross-sectional area is increased simultaneously with a change in its profile. The invention makes it possible to reduce material and energy costs and realize a wider range of product shapes and sizes. E. Kh. Shakhpazov and B. A. Korotkov. Patent No. 2158654 MPK 7 B 22 D 11/12, published 2000.10.11. Patent-holder I. P. Bardin Central Scientific Research Institute of Ferrous Metallurgy. Sinter composed of metallurgical cobalt has been developed.The sinter consists of a primary and secondary particles. The primary particles are oval and measure 0.5‐2 μm in size, while the spherical secondary particles are agglomerated and have a diameter within the range 3‐50 μm (preferably 5‐20 μm). The specific surface of the sinter is 2‐6 m 2 /g. A method has also been developed to obtain metallic cobalt sinter. The method involves having a cobalt salt with the general formula CoX 2 (X denotes Cl ‐ ,N O 3 ‐ , and/or 1/2 SO 4 2‐ ) react with a reagent and be reduced to metallic cobalt sinter. The salt continuously reacts with an aqueous solution or suspension of a carbonate and/or bicarbonate of an alkali metal and/or ammo

Simple (Lennard-Jones) and polymer nanosized droplet spreading over structured (heterogeneous) solid substrates has been simulated on the basis of isothermal molecular dynamics. Three types of modeling substrates with mesoscopic nanosized heterogeneities have been used: stripped surfaces, high-energy surfaces with regularly quadratic low-energy inclusions and low-energy ones with quadratic high-energy inclusions. It has been shown that spreading kinetics and final droplet configurations may be greatly influenced by the mesoscopic structure of the substrate. It has been also found that the macroscopic Cassie law is not always qualitatively satisfied for a substrate with mesoscopic heterogeneities.

Thermodynamic stability conditions (following from non-negativity of the second variation of the free energy) have been analyzed for two cases: (i) the nanoscale region when the surface tension depends on the particle size; (ii) the limiting case when the surface tension becomes equal to its macroscopic value. One has shown that the thermodynamic condition of mechanical stability of small objects relates its effective surface tension with the isothermal compressibility of the corresponding bulk maternal phase.

A method has been proposed for making low-carbon cold-rolled steel strip.The method provides for cold rolling with a prescribed amount of reduction per pass, tension on the strip between the stands, and cutting of its sides by disk shears. The reduction in the first pass is 32‐33% for the rolling of strip having the smallest cross section. In this case, the initial yield point σ y = 215‐415 MPa and the total relative reduction after four passes is 68‐72%. After the first pass, the size of the cross-section of the strip is restricted by the concave surface of the rolls. The amount of tension between the stands is established in relation to the average theoretical yield point σ y ′ = σ y + 33.5·e 0.6 MPa. After the nth pass, the yield point is equal to σ n = k·σ y ′. Here, the tension on the strip during the cutting of the edges is σ 0 = (0.34‐0.46)σ y . The disk shears are installed so that they have a radial overlap of Δ = 0.5h, where e is the total relative reduction in the nth pass, %; k is a proportionality factor; σ y  is the average yield point of the metal being cut, MPa; h is the thickness of the strip, mm. The method expands the capabilities of continuous cold-rolling mills by improving the quality of strip having the smallest cross-sections. A. A. Morozov, R. S. Takhautdinov, A. I. Antipenko, et al. Patent No. 2147943 MPK 7 B 21 B 1/28, published 2000.27.04. Patent-holder Magnitogorsk Metallurgical Combine. A method has been proposed for using rolling-mill rolls. The method can be used on mills designed for the cold rolling of steel sheet. It entails repeating a sequence of operations numerous times: grinding of the body of the roll; assembly of the roll with its chocks on bearings; operation of the roll in the stand; disassembly. After the roll has been used, i t and the chocks are exposed to jets of water with a temperature of 65‐95°C. The water is delivered at a pressure of 25‐45 MPa for 2‐7 min. While the water is being delivered, the roll is moved back and fourth at a rate of 1.2‐1.8 m/min within the range of the jets. The method improves the durability of rolling-mill rolls and their bearings. V. P. Nastich, A. A. Ugarov, V. P. Vinogradov, et al. Patent No. 2147944 MPK 7 B 21 B 28/02, published 2000.27.04. Patent-holder Novolipetsk Metallurgical Combine.