Scratch-Induced Deformation of Poly(methyl methacrylate) under Dry and Wet Conditions

Abstract

ABSTRACT Poly(methyl methacrylate) (PMMA), transparent thermoplastic materials similar to glass, was applied in several wide-ranging applications such as cell phone display screens, transparent windows and signboards. However, they are soft and easily appeared poorly transparent properties when getting scratches on their surfaces of applications under dry and wet conditions. Therefore, in this research, the features of PMMA materials after scratch damage was studied by diamond scratch tester under various loads at different environments. The optical microscope was thus applied to investigate the morphology of scratch track on the materials. In addition, the scratch resistance was analyzed by the scratch tester. From the results, the scratch depth was increased with an increasing load in both conditions as well as with the higher stress concentration. The scratch hardness, specific scratch wear rate and scratch coefficient of friction related with the applied load that it affected elastic and plastic deformation state