Laws of the structure formation, as well as the strength properties and thermal stability of vacuum condensates of the Fe-W system have been studied. It has been found that the alloying of iron foils with tungsten to 1 at % makes it possible to disperse the grained structure of the condensates to nanometric dimensionality and to markedly enhance their strength properties and recrystallization temperature. Thus, the foils contain ing ~0.8% tungsten and grains of about 50 nm in size exhibit the hardness 5.5 GPa and recrystallization tem perature 800°C. These results can be used to devise compositions of the steels designed for subsequently obtaining high strength and thermostable nanostructural states.

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The structure and strength properties of two-component copper-based Cu-Co, Cu-Mo and Cu-Ta vacuum condensates are investigated. It is shown that cobalt, molybdenum and tantalum disperse the grain structure of the copper matrix to submicron and nanometer dimension, form supersaturated solid solutions in the copper fcc lattice and heterophase structures. A decrease in grain size of condensates is explained by the formation of adsorption layers by the atoms of doping elements on the surface of the copper matrix metal growing grains. The Hall-Petch dependences for the yield strength are built. The dependences for Cu-Mo and Cu-Ta condensates have greater slope than a similar function for the single-component copper. The observed effect is explained by the influence of monolayer grain boundary segregation of molybdenum and tantalum atoms and multilayer segregation of Co atoms.

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