Structure and strength of vacuum Cu-Mo condensates

PhD student Maria Zhadko (Ukraine)

Video was recorded during the 7th International research and practice Conference "Nanotechnolgy and Nanomaterials" (NANO-2019)

One of the structural factors that affect metal properties is grain-boundary segregation of atoms of alloying elements, impurities and modifiers, which can have a strong influence on the structure formation, strength, physical and chemical properties and thermal stability. Their structural-phase state is associated with adsorption processes at the interfaces between phases and grains. These processes have common patterns with adsorption phenomena on free surfaces. Earlier studies on the preparation of nanostructured thermally stable Fe-W [1], Al-Fe [2], Cu-Ta [3] condensates showed that the maximum dispersing effect of alloying elements, the highest recrystallization temperatures and strength properties of these objects appear at certain contents of tungsten in iron, tantalum and molybdenum in copper, iron in aluminum, which sufficient to form grain-boundary segregation in the form of monoatomic adsorption layers. Langmuir-McLean monolayer adsorption mechanism, one of the features of which is the ability of atoms of a segregating substance to increase the cohesive strength of grain boundaries due to the formation of strong interatomic bonds with atoms of the matrix metal draws special attention in connection with the possibility of improving the efficiency of grain-boundary hardening.

In this regard, objective of the present study is to understand processes of the structure of two-component vacuum Cu-Mo condensates formation, structural-phase state of grain-boundary segregations of molybdenum atoms and strength properties of these objects, which were obtained by electron-beam evaporation from different sources and subsequent crystallization on non-orienting substrates in vacuum at a pressure of ~ 10-3 Pa.

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  2. Lutsenko E. V., Kreshchenko V. A., Rud’ M. D., Sobol’ O. V., Glushchenko M. A., Zubkov, A. I. Segregation refinement of the grain structure of aluminium and its alloys //Metallofiz. Noveishie Tekhnol.-2017.-39, N 5.-P. 607620.

  3. Zubkov A. I., Zubarev E. N., Sobol’ O. V., Hlushchenko M. A., Lutsenko E. V. Structure of Vacuum Cu-Ta Condensates // Phys. Met. Metallogr.-2017. -118, N 2.-P. 158163.