Surface coatings and thin films are popular in increasing engineering functionality, wear resistance, and corrosion protection of engineering components. Their thin nature makes traditional mechanical tests inapplicable in testing their performance. Nano-scratch testing is a sensitive and controlled method of evaluating the performance of coatings through the simulation of contact and sliding at the nanoscale. The knowledge of the behaviour of scratch-induced damage and adhesion assists in the optimization of the design of coatings and long-term reliability.
Principle of Nano-Scratch Testing
The nano-scratch test is a procedure whereby a hard indenter or diamond is used to slide on a coated surface with a gradual increase in the force applied. The ensuing deformation, cracking, or delamination is informative about coating mechanical activity and bonding strength.
Assessment of Adhesion and Cohesion
Critical loads in testing represent the beginning of coating failure or exposure to the substrate. These parameters are applied to the comparison of the quality of adhesion and internal cohesion of other systems of thin films.
Evaluation of Scratch Resistance
The resistance of a coating to scratching displays its ability to resist mechanical touch and wear. Nano-scratch testing quantifies scratch intensity, frictional reaction, and harm progression.
