Elasticity & resistance deformation - bend, cupping & impact
Elasticity and resitance to deformation are part of the key physical properties required in the coatings industry. 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 discoloration.
Impact Tes - 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 Tes - A coated metal sheet 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. The end-point is when the coating begins to crack.
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