IZOD TEST

The Izod Test
The Izod test is has become the standard testing
procedure for comparing the impact resistances of
plastics. While being the standard for plastics it
is also used on other materials.

The Izod test is most commonly used to evaluate the
relative toughness or impact toughness of materials
and as such is often used in quality control
applications where it is a fast and economical test.
It is used more as a comparative test rather than a
definitive test. This is also in part due to
the fact that the values do not relate accurately to
the impact strength of moulded parts or actual
components under actual operational conditions.
What Does the Izod Test Involve?
The Izod test involves striking a suitable test piece
with a striker, mounted at the end of a pendulum. The
test piece is clamped vertically with the notch facing
the striker. The striker swings downwards impacting the
test piece at the bottom of its swing.

Some Izod impact testers are equipped to be able to
utilise different sized strikers, which impart different
amounts of energy. Often a series of stri8kers may be used
to determine the impact energy, starting with small strikers
and working up until failure occurs.


Izod Tests at Different Temperatures
Tests are often performed at different temperatures to more
closely simulate the actual service conditions. In the case of
low temperature tests, specimens may are kept in a freezer
until their temperature has equilibrated. They are then
immediately removed and tested within seconds of removal from the freezer.