Binary system Fe[100-x] - Cu[x], x = 0,1... 0,9 with a limited
solubility of elements that has positive enthalpy of mixture was
investigated. The mechanical alloying proceeds through compacting and
plastic deformation of heterogeneous mixtures of powders by the shear
under pressure method at a pressure of 6 - 8 GPa, at room temperature.
Combined investigation of the structure and properties of mechanically
alloyed samples was carried out by x-ray, Mössbauer, TEM spectroscopy,
with magnetometry and metallography also being applied.
Experiments have shown, that cold heavy deformation, such as of 7 - 10
units of true (logarithmic) scale, under high quasihydrostatic
pressure P ł (0,01 ... 0,50) ˇ m , where m - the bulk modulus, results
in the mechanical alloying of components and allows to receive
porous-free samples uncontaminated by impurities from anvil punches.
The analysis of data has allowed to make a conclusion about
deformation-like character of the nanocrystalline structure formation
in the whole range of concentrations of the initial components mixed.
Study has showed that the structural and phase state of the samples,
their physical and mechanical properties depend on the modes of
processing and initial concentration of the components in the
mixtures. Single-phase solid a -solutions on the basis of iron bcc and
e - solutions on the basis of copper fcc were received. The two-phase
state of the samples (bcc + fcc) was formed in the range of
intermediate concentrations of the components of approximately x = 0,2
- 0,4. The size of nanocrystallites depends on both modes of
processing and phase structure of solution and falls in the range from
10 up to 40 nm.
Thus, the intensive deformation under high pressure results in the
formation of the nanocrystalline solid solutions of nonequilibrum
concentrations in the iron - copper system.