Performance of europium in microstructural modification of high strength lightweight aluminum components

Abstract

Even though all rare-earth elements are within the atomic radii range of Impurity Induced Twinning Model, Europium (Eu) is the only one capable to fully modify the plate like eutectic silicon into fine fibrous morphology. Nevertheless, quantitative information on the microstructural features and mechanical properties of the Eu modified cast Al alloys seems to be scarce. In view of the fact that the process variables alter the microstructures of the casting Al alloys, a study was conducted on the microstructural features of Eu modified A360 Al alloys in order to correlate the parameters such as type and amount of microconstituents and defects to the strength and fracture resistance of the developed alloys. To attain the optimum properties of the cast Al alloys in terms of the strength and fracture resistance, SDAS values are required to be minimized. High cooling rate scale down the dimensions of the Si particles and intermetallics and therefore improve the mechanical properties and fracture resistance of the alloy. Keywords: A360 alloy, Microstructure, Eu, Modification