Interfacial microstructure and nucleating mechanism of melt-spun CeB6/Al composite inoculant

The microstructure of the CeB6/Al interface in an Al-Ce-B alloy prepared by melt-spinning was investigated by scanning electron microscope (SEM) and transmission electron microscopy (TEM). The in situ synthetic CeB6 particle in Al melt generally shows cubic morphology in which the naked surface is (220) plane. After adding in Al melt during inoculation, a well-bonded interface was formed between the CeB6 particle and the Al crystalline matrix. The experimental observation on the degree of mismatch between Al (220) plane and CeB6 (220) plane was highly accorded with the theoretic calculated value. It was suggested that the surface of CeB6 particle is the potential nucleant substrate of Al crystal. As a result, the grain size of aluminum was significantly decreased by addition of CeB6/Al inoculant ribbons with a very small ratio of 0.3% in weight. (C) 2017 Elsevier B. V. All rights reserved.