| Elasticity and resistance to
deformation are part of the key
physical properties required in the
coatings industry today.
Essentially there are three different
test methods which are used to
determine a coating’s performance
under different deformation
conditions. |
Bend Test : A coated metal sheet
is bent over a cylindrical or conical
mandrel and the coating observed
for cracks and discolouration.
Impact Test : A coated metal
sheet is placed beneath a falling
weight and the resultant damage
caused by the deformation is
observed. The impact test method
is used to identify how the coating
performs under a rapid
deformation process.
Cupping Test : A coated sheet
metal is subjected to a gradual
deformation by a polished die. This
deformation is caused by the die
being pushed from beneath the
coating – i.e. from the reverse side
of the sheet metal. The end-point
is when the coating begins to
crack. |