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This study addresses the sensitivity of material removal regimes in 5083-Aluminum alloy to interactions mechanisms generated during Multi-Scratch Test (MST). A testing device using three conical indenters was firstly developed. Four attack angles and four normal loads ranging, respectively, in 10-60° and 10-25 N, were considered for conducting the experimental trials. The scratch velocity was kept constant to 210 mm min -1 and the maximum scratch distance to 25 mm. The model, developed upon ABAQUS/Explicit, uses JohnsonCook approach for describing both material behavior and damage evolution. Single Scratch Test (SST) and MST reveal same wear regimes, namely, (i) "ploughing", (ii) "transition", and (iii) "cutting" whereas a significant difference was observed in the material removal maps.While ploughing domain neatly decreases to the detriment of transition domain when passing from SST to MST, cutting domains still remain quite comparable. The indenter attack angle is depicted as the most dominant factor in apparent friction coefficient. The three dominating regimes were successfully predicted, using the FE model, in close correlation with tribological parameters. The model was found very useful to highlight the significant role of the separation distance on controlling material flow and damage within the grooves' junction.

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This study suggests a micromechanical approach to scrutinize the glass fiber reinforced polyester (GFRP) composite tribological behavior. A single indenter scratch test (SST) using spherical tip conical indenter was adopted. The 3D finite element (FE) model was developed into ABAQUS/Explicit commercial code. Both material behavior and damage of polyester matrix and glass fiber was modeled using the Johnson Cook behavior law. Nevertheless, the fiber/matrix interface behavior is described using the cohesive zone approach via the cohesive elements. The elementary wear mechanisms owing to the SST were appraised at different attack angle and normal load by the mean of scanning electron microscope (SEM). In this work, the material removal map was built to emphasize the correlation between the tribological parameters, particularly the attack angle and the normal load, and the material removal process. The numerical results emphasized the significant effects of the attack angle and the penetration depth on the transition of the wear mechanisms from ploughing to composite damage. The experimental wear mechanisms and the predicted elementary wear mechanisms seem to be in a good agreement.

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