Name
Dmitrenko Dmitriy Valeryevich
Scholastic degree
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Academic rank
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Honorary rank
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Organization, job position
Kuban State Technological University
Web site url
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Articles count: 3
The article is dedicated to the determination of
conditions for solid bodies’ fragmentation, providing
minimal size of particles by means of their mechanical
dispersion through the example of powders of titanium
carbide (TiC), cubic boron nitride – borazon (CBN)
and boron carbide (B4C). The theoretical and practical
aspects of the process of mechanical fragmentation of
particles of solid powder materials in ball mill for their
further utilization in furnace charge for high-speed
gas-flame sputtering of wear-resistant composite
materials are examined in the article. Methods of
preliminary calculation of minimum allowable size of
solid particles of powder materials during mechanical
fragmentation, based upon Griffiths’ mechanical
theory of rapture using experimental data for hardness
of material and its yield are proposed and theoretically
substantiated. There we have the results of
experiments on mechanical fragmentation of titanium
carbide in attritor, boron carbide and cubic boron
nitride in centrifugal planetary mill, confirming
correctness of theoretical propositions and calculations
are set out. Recommendations on mechanical
fragmentation of solid powder materials in ball mills
are formulated as well
The mechanical activation allows creating a active
state in a solid, opening the prospect for holding and
accelerating the chemical reactions between solids and
getting materials in a nonequilibrium state. As a result
of mechanical activation of the powder compositions
of the active phase transformations occur in them,
which lead to the formation of solid solutions and
various intermediate connections, providing dispersion
and dispersion hardening of materials included in the
composition. The results of the study of the
granulometric composition, the phase transformations
and structure evolution in multiphase materials with
SME Ni-30%at.Ti-20%at.Hf and Ni-33%at.Ti-
18%at.Zr at different stages of the process of
mechanical activation carried out in planetary ball mill
the centrifugal type is represented in the article.
During mechanical activation, a composite mix is
assimilated by the particles of processed material input
of mechanical energy in the form of new interfaces,
defects of the crystal lattice. At collision of particles
and grinding bodies in contact high local temperature
and pressure occur, which in some cases can lead to
melting of the most fusible components. When a local
increase in temperature between the particles of
titanium, hafnium, zirconium and carbon solid-phase
reactions become possible due to diffusion of atoms of
one component into the crystal lattice of the other.
Experimental studies have shown that the use of
mechanical activation allows creating an effective
technology of preparation of the starting material for
high-speed flame spraying
In the article the technology of obtaining carbide steel with hot punching porous billets produced by shock compaction, based on no form powders is described, the structure and properties of the obtained composite material are studied, the parts with enhanced mechanical properties are presented