This International Standard specifies a test method to determine the ability of a cured adhesive (if necessary with a primer) to adhere to a substrate with a certain surface finish, or which has been subjected to a specific surface preparation, using the "three-point bending method".
This standard is only applicable to quality assurance and only to substrates which are rigid or resistant enough to bending, such as steel or aluminium alloys. For other substrates, the thickness is adjusted to the modulus of elasticity or a suitable stiffener is used.
The adhesive is allowed to cure without the application of pressure in order to obtain the thickness needed to provide sufficient rigidity, otherwise a bonded reinforcing piece of the same material and the same thickness as the substrate is substituted for the block of adhesive.
This test method is not suitable for film adhesives.