In situ microtomography investigation of microstructural evolution in
Al-Cu alloys during holding in semi-solid state
(1. Australian Research Council Centre of Excellence for Design in Light Metals, Materials Engineering,
The University of Queensland, Brisbane Queensland 4072, Australia；
2. Université de Grenoble, Science et Ingénierie des Matériaux et Procédés,
Génie Physique et Mécanique des Matériaux, UMR CNRS 5266, Grenoble INP,
Université Joseph Fourrier, BP46, 38402 Saint-Martin d’Hères Cedex, France；
3. European Synchrotron Radiation Facility, 6 rue Jules Horowitz, BP220, 38043 Grenoble Cedex, France)
The University of Queensland, Brisbane Queensland 4072, Australia；
2. Université de Grenoble, Science et Ingénierie des Matériaux et Procédés,
Génie Physique et Mécanique des Matériaux, UMR CNRS 5266, Grenoble INP,
Université Joseph Fourrier, BP46, 38402 Saint-Martin d’Hères Cedex, France；
3. European Synchrotron Radiation Facility, 6 rue Jules Horowitz, BP220, 38043 Grenoble Cedex, France)
Abstract: The aim of this paper is to report the results of experiments carried out on Al-Cu alloys with different Cu contents, studying the microstructure evolution during holding in the semi-solid state. The 3-D microstructure was observed by in situ X-ray microtomography carried out at ESRF Grenoble, France. The variation of the solid-liquid interface area per unit volume during holding was determined. In addition, local observations show that two coarsening mechanisms of the solid particles occur simultaneously: dissolution of small particles to the benefit of larger ones by an Ostwald-type mechanism and the growth of necks between solid particles due to coalescence. These observations confirm that in situ X-ray tomography is a very powerful tool to study the microstructure evolution in the semi-solid state and the influencing mechanisms in real-time.
Key words: Al-Cu alloys; microtomography; remelting; microstructure