Mechanism of temperature rise due to crazing evolution during PMMA scratch

Dramatic temperature rise has been observed at the surface facture area during the scratch of brittle poly(methyl methacrylate) (PMMA). However, the strain energy accompanied with the macroscopic linear elastic fracture is inadequate to explain the significant temperature change. To describe this phenomenon, the crazing related energy dissipation mechanism considering the evolution of microscopic crazing is proposed in this paper. The algorithm to calculate the crazing-induced temperature rise is presented. After validated by the experiment and finite element (FE) simulation for the tension of a thin plate with a circular hole, the proposed approach is utilized to investigate the scratch-induced-temperature rise with the combination of FE simulation. The frictional heating and macroscopic plastic deformation make their contribution for the temperature rise at relative small scratch load. The energy dissipated by the crazing process plays a dominating role for the scratch-induced fracture. Those findings provide meaningful insight for understanding the mechanism of temperature rise during polymer scratch. (C) 2020 Elsevier Ltd. All rights reserved.