title: Multiscale tomographic analysis of heterogeneous cast Al-Si-X alloys.
abstract: The three-dimensional microstructure of cast AlSi12Ni and AlSi10Cu5Ni2 alloys is investigated by laboratory X-ray computed tomography, synchrotron X-ray computed microtomography, light optical tomography and synchrotron X-ray computed microtomography with submicrometre resolution. The results obtained with each technique are correlated with the size of the scanned volumes and resolved microstructural features. Laboratory X-ray computed tomography is sufficient to resolve highly absorbing aluminides but eutectic and primary Si remain unrevealed. Synchrotron X-ray computed microtomography at ID15/ESRF gives better spatial resolution and reveals primary Si in addition to aluminides. Synchrotron X-ray computed microtomography at ID19/ESRF reveals all the phases ≥ ∼1 μm in volumes about 80 times smaller than laboratory X-ray computed tomography. The volumes investigated by light optical tomography and submicrometre synchrotron X-ray computed microtomography are much smaller than laboratory X-ray computed tomography but both techniques provide local chemical information on the types of aluminides. The complementary techniques applied enable a full three-dimensional characterization of the microstructure of the alloys at length scales ranging over six orders of magnitude.
authors: Materials Division, Directorate of Technology, PINSTECH, P. O. Nilore, Islamabad, Pakistan.
authors: Z
authors: Z
authors: Asghar
authors: German Aerospace Centre - DLR, Institute of Materials Research, Linder Höhe, Cologne, Germany.|RWTH-Aachen, Aachen, Germany.
authors: G
authors: G
authors: Requena
authors: IMDEA Materials Institute, C/ Eric Kandel 2, Getafe, Madrid, Spain.
authors: F
authors: F
authors: Sket
keywords: Casting; microstructure; piston alloys; tomography