Thin Film Tensile Testing App Note


We have received a couple more great application notes involving our Tensile Testing Stage the TST350.

These two come from the folks at the Ecole Polytechnique Federale de Lausanne (EPFL) in Switzerland.
Here's the 'Introduction' from the App Note,
'Fragmentation Test Method for Adhesion Analysis of Coatings In Situ in a Microscope'.
You can read the full application note on our website.
'Mechanical integrity is a key attribute of coatings, which should not crack and delaminate during processing and during service life. Numerous methods are available to determine the adhesion of coatings, including tape and pull-out tests, and indentation and scratch techniques. The accuracy of these methods is however compromised by the presence of 'third body interactions', such as indenter-coating friction in case of scratch and indentation tests, or adherent-coating traction in case of peel and pull-out tests. The fragmentation test method detailed in the present note is free of third-body interactions. It enables quantifying the cohesive properties (which control cracking) and the adhesive properties (which control delamination) of coatings on high-elongation substrates. The method has been used to analyze a broad range of coating/substrate combinations, including inorganic coatings on polymers [1-3] and steel (e.g, [4]) and organic coatings on polymers (e.g., [e.g, [5]). The following section introduces the theory of coating fragmentation and calculation of the adhesive strength. The experimental conditions are detailed in a further section. Finally two application examples are given to illustrate the method, with focus on adhesive strength of an organic coating on a PET substrate, and a transparent electrode on a PEN substrate.'
With Thanks to Dr. Manfred Feustel of Resultec Analytical Equipment for his collaboration.