What Does Tensile Pull-Off Adhesion Test Mean?
A tensile pull-off adhesion test refers to a kind of adhesion test that is used in paint and coating industries to determine the resistance of paints and coatings to coated substrates. Coated substrates are usually metals, plastics, concrete, wood and glass.
This adhesion test helps to measure the effectiveness of a coating system or the consequence of additives and/or primers. A cost-benefit analysis can be done on varied primers, adhesives or coatings through conducting this test. A pull-off adhesion test is cost-effective for large projects.
Corrosionpedia Explains Tensile Pull-Off Adhesion Test
A tensile pull-off adhesion test is done to measure the resistance of a coating to separate from a substrate applying a perpendicular tensile force. This measured pull-off force delivers an indication of the strength of the adhesion between the coating and the substrate. This test is largely used in the construction industry. This adhesion test needs specialized equipment and takes a comparatively longer time to perform.
In this test, the adhesion of a coating of any product is determined by evaluating the least tensile stress required to detach or rupture the coating perpendicular to the substrate. The test is performed by securing loading fixtures (dollies) perpendicular to the surface of a coating with an adhesive.
If there is an adhesion issue on old substrates, like contaminated concrete in old automotive workshops, this test can be performed on samples before applying a full-scale application. Pull-off adhesion strength assessments depend on two things: material and instrumental parameters. The strength of adhesion bonds between the loading fixture, coating system and the substrate—or the cohesive strengths of the adhesive, coating layers and substrate—limit the assessments. This test is destructive and requires spot repairs.