The solidification of two binary alloys, In-10Sn and Sn-13Pb, has been investigated by X-ray diffractometry (XRD) at high temperature. The high temperature X-ray camera used in the experiments is mounted on a diffractometer, allocates a sample holder apt to contain molten metals and can operate up to 1600°C in vacuum or in a controlled atmosphere of inert gas. Melts have been slowly cooled down to the liquidus temperature and XRD spectra recorded step by step. The temperature was kept constant while XRD data were collected. From the spectra the radial distribution functions (RDF) have been then determined for each temperature. Experiments showed that atomic clustering forms in the melt immediately before the appearing of the first solid and that the structures in the liquid are correlated to those of the solid. Experimental problems connected to real-time monitoring of phase transformations involving liquid metals have been examined. To avoid convective motions in the liquid and to achieve the best experimental conditions, it is discussed the possibility to perform the same experiments under conditions of reduced gravity aboard the International Space Station (ISS).
Montanari, R., Gauzzi, F. (2009). XRD investigation of binary alloys solidification. ANNALS OF THE NEW YORK ACADEMY OF SCIENCES, 1161(1), 407-415 [10.1111/j.1749-6632.2008.04317.x].
XRD investigation of binary alloys solidification
MONTANARI, ROBERTO;GAUZZI, FRANCO
2009-01-01
Abstract
The solidification of two binary alloys, In-10Sn and Sn-13Pb, has been investigated by X-ray diffractometry (XRD) at high temperature. The high temperature X-ray camera used in the experiments is mounted on a diffractometer, allocates a sample holder apt to contain molten metals and can operate up to 1600°C in vacuum or in a controlled atmosphere of inert gas. Melts have been slowly cooled down to the liquidus temperature and XRD spectra recorded step by step. The temperature was kept constant while XRD data were collected. From the spectra the radial distribution functions (RDF) have been then determined for each temperature. Experiments showed that atomic clustering forms in the melt immediately before the appearing of the first solid and that the structures in the liquid are correlated to those of the solid. Experimental problems connected to real-time monitoring of phase transformations involving liquid metals have been examined. To avoid convective motions in the liquid and to achieve the best experimental conditions, it is discussed the possibility to perform the same experiments under conditions of reduced gravity aboard the International Space Station (ISS).I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.