Scratch-tester Brucker UMT-X

Measurement of adhesion of thin films and coatings

A scratch test is a method used to evaluate the adhesion between a coating or thin film and its substrate. The test involves applying a controlled force through a sharp diamond tip while dragging it across the surface to assess the coating's adhesion to the substrate. An indenter is pressed against the coated surface with an increasing force until the coating delaminates, fractures, or shows signs of adhesion failure. The force at which the failure starts is labeled as the critical load (Lc). The scratch test is a standardized approach for quantitatively assessing coating adhesion under controlled conditions.