Influence of magnetic field on the mechanical behavior of friction stir processed paramagnetic alloy

Abstract

The study investigated the influence of an externally applied static magnetic field (MF) on the mechanical behavior of a friction stir processed paramagnetic 1100 aluminum (Al 1100) alloy. The aim was to take advantage of the solid-state friction stir processing (FSP) technique to modify the microstructure and further improve the properties by testing in the presence of MF. Al 1100 was tested in tension under different static MFs (B = 0, 150, 1000, 1400, 1800, and 2200 Gauss) perpendicular to the stress axis. The strong effect of a comparatively weak static MF was observed on the elongation of both base and processed Al 1100 alloy, in both rolling and transverse directions, attributed to the magneto-plasticity effect (MPE) where the motion of dislocations in crystals is influenced in the presence of magnetic fields. Amongst the different mechanisms associated with MPE, the major effect in the current study was observed from the magnetization force, spin transition, and increase in strain energy of dislocations. This knowledge will open new lanes to improve the properties of a processed sample by exposing it to an MF which is a non-contact, pollution-free route; saving time and cost by avoiding in-between thermo-mechanical steps to break the cast microstructure.