Characterisation of thin film adhesion with the Nano-Scratch Tester (NST)

摘要

As the thickness of functional coatings decrease to satisfy structural and protective needs in thin film applications, quantitative instrumentation has become a necessity for adequate evaluation of system properties, particularly scratch resistance and adhesion at the film-substrate interface. The Nano-Scratch Tester (NST) is a new instrument overcoming the limitations of both the classical stylus scratch test (normal force range) and the scanning force microscope (SFM) techniques (short sliding distances) allowing for scratch lengths of up to 10 mm. Tangential force and penetration depths are simultaneously measured during the scratch process. To assist in the inspection of the deformed or damaged area, a scanning probe microscope may be integrated into the system. Experimental results are presented for a range of thin film adhesion applications including clear coatings and thin, multi-layer magnetic laminates. The results indicate very good reproducibility and confirm the application of this instrument to accurately characterization adhesion, elasticity, and mechanical integrity in coated systems where the film thickness is less than 1 μm.