Scratch resistance and localised damage characteristics of polymer surfaces - a review

The "Scratch Test" is, arguably, the earliest and amongst the now most widely used techniques for evaluating a wide range of surface mechanical properties. Some of the areas where this test has been successfully used in the engineering field, both by research and industry, include the determination of the relative hardness of materials. characterizations of coatings, paints and thin-films, modeling of the wear of materials and the estimation of different material deformation characteristics when subjected to hard asperity damage. In this paper we have reviewed the "state-of-the-art" in the scratch method for polymeric materials. The paper provides some important theoretical models that have been developed in the field of scratching for material property characterizations. Results from different types of scratch tests (macro, micro and nano scales) on a range of polymeric materials are presented with critical discussion on the usefulness of each result. Finally, various areas for further research in scratching of polymer surfaces have been identified.