Correlation between the anisotropy of an AA2021-T351 aluminium rolled thick plate and the occurrence of the stick-slip phenomenon

The stick-slip phenomenon is a dynamic instability that appears at the contact interface of two sliding surfaces. Its occurrence is influenced by the relative sliding speed, the contact pressure, and the system rigidity, but also by the state of contact between the two sliding surfaces. The present paper aims to study the influence of the anisotropy of an aluminium AA2021-T351 plate on the stick-slip phenomenon. For this, using the CETR UMT II tribometer, linear sliding tests have been performed on the aluminium alloy thick plate surface using a cylindrical pin made of ultra-high-molecular-weight polyethylene (UHMWPE) along three directions: a longitudinal one, corresponding to the rolling direction of the sample (0°), a transverse one, perpendicular to the rolling direction (90°), and a median direction (45°). Varying the sliding speed, the contact pressure, and the system rigidity, it was possible to observe the influence of the material anisotropy on the specific parameters of the stick-slip phenomenon.