Abstract: Severe plastic deformation (SPD) methods for the production of bulk fine-grained material are expensive and there is need to explore cheaper method like cold rolling for improved fatigue behaviours. In this study AA1200 aluminium alloy was cast, homogenized and cold-rolled between 10-50 % thickness reduction. The rolled sample were subjected to tensile and fatigue tests. Samples were examined using a Digital Metallurgical microscope. The result shows that SPD at ambient temperature produces fine crystals that promote fatigue life. In the rolling direction, the fatigue life of AA1200 Aluminium Alloy increases with deformation and decline momentarily before climbing to peak at 40% reduction. The initial deformation directly correlates with the expected fatigue life of the components in service under low stress cycle. As fatigue stress increases, the fatigue life decline and at low fatigue stress, the fatigue life is higher. The fractured surfaces reveal non-uniformity (anisotropy) in the distribution of phases in the matrix along its length in the rolling direction attributed to variations in sheet thickness, composition and grain size.
Authors: O.M. Oyekeye, S.O. Adeosun, J.S. Ajiboye, and A.A. Agbeleye
Keywords: Strength, fatigue life, microstructure, aluminium alloy, cold rolling