An experimental study of the nano-scratch behaviour of poly(methyl methacrylate)

An experimental study of poly(methyl methacrylate) (PMMA) is described with the aim of investigating the potential for the formation of wear particles by the interaction of multiple scratches under plastic ploughing condition s. The work was carried out using a nano-indenter fitted with a Berkovich p robe. It was found that orthogonally intersecting scratches produced lumpy protuberances which could act as a precursor for wear particles. However, p arallel scratches in close proximity resulted in a self-protective mechanis m due to the load carrying capacity of the strain hardened pile-up from nei ghbouring scratches. (C) 2001 Elsevier Science B.V. All rights reserved.