NANOSTRUCTURE FORMATION ON THE SURFACE OF RAILWAY TRACKS AND
WHEELSETS,
L. Perchuc, W. L/ojkowski High Pressure Research Center UNIPRESS,
Warsaw, Poland
It is clear that the spin at the tread of drive wheels appear always.
Under operation conditions a phenomenon of macrospin and side-slipping
which causes an excessive wear of wheel treads (flat spots on a
rolling tread) is especially undesirable and harmful. A railway wheel
flat is a flat spot on the rolling surface of a wheel caused by its
unintentional sliding on the rail. Under certain sliding conditions,
nanostructure, which is a brittle phase of carbon steel, will form
around such a flat. The presence of nanostructure often leads to
cracking and spalling of the material in the tread of a rolling wheel
having a flat. The better knowledge about the process of formation of
nanostructure around a wheel flat, and about the ensuing spalling,
will facilitate money-saving improvements in material of wheel and
will enable to increase safety.
There are many theories concerning formation nanostructure on the
surface wheel tread and rail. The theory the most known among them
assumes that it's caused by the heat being produced during sliding of
the wheel on the rail at occurring simultaneous intensive cooling. A
second theory of that nanostructure formation assumes of the reason a
pressure on the wheel on the rail.
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