•Lubricated and dry sliding tests were conducted on AA5083/AISI-52100 material pair.•The effect of initial surface topography on the wear and friction behavior was discussed.•RS approach was applied ...to correlate crater area, cycle number and mean absolute profile slope.•The formation of BUL improve contact condition and provokes transition in wear mechanisms.•Analysis of crater area contributes for controlling friction and wear when sliding dry.
This paper discusses the effect of surface topography and lubrication on the tribological behavior of AA5083 alloy for wide range of average roughness, Ra. Reciprocating sliding tests were conducted under lubricated and dry regimes over different pre-textured surfaces using AISI-52100 steel ball under two contact pressures. Scanning Electron Microscope (SEM) and profilometer were employed for characterizing wear land and type. Particularly, the effect of the mean absolute profile slope Δa of AA5083 plates on friction and wear was investigated within an early repetitive sliding stage. Experimental results show that a close correlation was found between the tribological behavior and the mean absolute slope, Δa, contrary to the average roughness, Ra, which shows a partial link. From SEM inspections, dry sliding correlates with the generation of ploughing over aluminum topographies, and with the formation of Built-Up Layer (BUL) due to adhesion over steel ball. However, lubrication, transforms material removal process over the ball from adhesion to abrasion which affects inevitably the initial topography. The evolution of crater area S − reflects high sensitivity to Δa. In order to predict the wear evolution, a mathematical model taking into account the impact of Δa and the number of sliding cycles (N) was developed using Response Surface Method (RSM).
Predicted crater area vs. the number of cycles and mean absolute profile slope obtained using RS approach. (a) Smooth, and, (b) rough surfaces at dry conditions, and, (c) Smooth, and, (d) rough surfaces at lubricated conditions. Display omitted
In this study, the micromechanical scratch behavior of unidirectional glass fiber reinforced polyester (GFRP) using several wear conditions was highlighted. Single-indenter scratch tests (SSTs) were ...carried out on GFRP composite material perpendicular (SST
) and parallel (SST
) to fiber direction. Damage modes dominating the material removal process (MRP) and friction exhibit significant sensitivity to both attack angle and normal load. From findings, damage modes and apparent friction coefficient substantially accentuate when increasing the attack angle. The inspections of the damage state at different testing conditions using a scanning electron microscope (SEM) reveal the dominating modes governing the MRP through the different phases. The response surface methodology (RSM) was adopted to develop a mathematical model based on the measured data. The RSM approach was found very promoting for predicting friction evolution versus attack angle and normal load. The proposed model reveals good ability not only in predicting apparent friction coefficient but also in detecting separately its ploughing and adhesive component. To emphasize the correlation between friction coefficient and MRP, the wear maps have been drawn up.
Tribological behavior of five different surfaces patterns, bioinspired from maize leaf skin, shark skin, snakeskin, pitcher’s structure and lizard skin, was investigated. Bioinspired surfaces have ...been printed using Fused Deposition Modelling (FDM) technology from a marked Poly Lactic Acid (PLA). Tribological tests were carried out using a reciprocating sliding device under dry conditions at room temperature. Particular interest was given to the investigation of the friction anisotropy as well as the wear mechanisms. The correlation between the apparent friction coefficient and the test conditions, particularly, the 3D printed bioinspired surface patterns and the number of cycles, was emphasized via the friction maps.
This attempt proposes a Finite Element Approach (FEA) to investigate the tribological behavior of glass fiber reinforced polyester composite. The 3D finite element model was developed upon ...ABAQUS/Explicit. The Johnson-Cook criteria were considered for describing the material behavior and damage of both fiber and matrix phases. The fiber/matrix interface behavior was, however, modeled using a thin cohesive zone (CZ). A mixed-mode loading concept was specially adopted to predict delamination propagation within the interface. The prevailing wear mechanisms owing to Multi-Scratch Test (MST) were inspected at variable load and attack angle, using scanning electron microscope (SEM). Wear maps were built to highlight the correlation between friction coefficient and wear mechanisms. Predictions of both elementary and interacting mechanisms showed excellent correlation with observations. It was revealed that material removal process varies sensitively with the dominating failure mode. The proposed approach exhibits good ability not only in predicting active mechanisms but also in detecting damage sequences governing the surface integrity during scratching.
