Mechanics
> Properties of Matter > Coefficient of
Restitution
DCS#
1R40.10(2)
COEFFICIENT OF
RESTITUTION - AMORPHOUS METAL
APPARATUS
plexiglas tubes with
aluminum
and Liquidmetal bases
202-16-E3
steel balls
202-16-E3
video camera
202
DESCRIPTION
Drop balls simultaneously onto
the aluminum and amorphous metal bases and compare the rebound
heights.
NOTES
The amorphous metal is an alloy
of
Zr, Be, Ti, Cu, and Ni, cooled from the molten state quickly
enough to
prevent crystallization. When the ball strikes the
amorphous
metal, little energy goes into deforming the metal, unlike the
crystalline metal in which energy is used in creating and
moving
dislocations. Pits can be seen on the surface of the
aluminum.
Liquidmetal is noteworthy in that it can be cooled more slowly
than
other amorphous metals - sufficiently slowly to be molded and
processed
using conventional techniques. See the links below for
applications.