Fatigue Limit Prediction Models of 6060 Aluminium Extruded Alloy

The fatigue limit stress prediction models make it possible to determine the durability of metals, considering experimental fatigue tests, mechanical properties, hardness, manufacturing technology (namely through intrinsic defects in the process), and empirical constants depending on the manufacturing processes and components' dimension. The manufacturing defects in the materials lead to failures at much lower applied stresses. Therefore, considering such defect features as input parameters in fatigue limit assessment is of primary importance. This work aims to develop fatigue life prediction models for extruded 6060 aluminium. The methodology used in this study is based on experimental work. The materials used were obtained from three extruded pieces of 6060 aluminium with different geometries (a rectangular section with smooth faces and recess faces and a solid rectangular section) and different thermal treatments (T1 and T4). In addition, the manufacturing defects of the stress concentration zones were studied. The algorithm to predict durability is based on the experimental results obtained. The Murakami, Ueno and Schӧnbauer models were studied. In conclusion, new models to predict fatigue limits were developed for the 6060-aluminium extruded alloy, considering different geometries and heat treatment.