The tungsten heavy alloys (WHAs) are metal–metal composites
consisting of nearly spherical particles embedded in
an Fe–Ni–W ductile matrix. The WHAs are fabricated by
liquid-phase sintering at about 1450–1500 ◦C. Their high
content of tungsten (90–97%) guarantees a high density
(16–18.5 g cm−3), a tensile strength over 950 MPa with a
relatively good ductility (5–30%). The WHAs are widely
used as radiation shields, gyroscope rotors, aircraft counterbalances
and penetrators [1,2].
During last years the research of WHAs has concentrated
on strengthening methods which do not compromise their
density. This is specially important in military applications.
Such an improvement can be obtained among other by strain
age-hardening.
In the present paper, transmission electron microscopy
(TEM) was used to reveal changes which occur in the
material microstructure after thermo-mechanical treatment.
The details of experiments concerning influence of
thermo-mechanical treatment on the properties of material
are described elsewhere