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G. Requena, Z. Asghar, H.P. Degischer, P. Cloetens:
"3D Study of Aluminides in Piston Alloys by Means of Light Optical and Synchrotron Tomography";
Talk: 43. Metallographie-Tagung 2009 Materialographie, Aachen - Deutschland; 09-16-2009 - 09-18-2009.

The microstructure of AlSi12NiCu piston alloys is formed by the alpha-Al, the eutectic Si and different Ni-Cu-Fe containing aluminides. Synchrotron microtomography can be used to characterize the complex 3D microstructure of these alloys. However, the similar X-ray absorption exhibited by aluminides with different Ni, Cu and Fe contents make it impossible to differentiate them by this technique. A method is developed to identify the phases and characterize the morphology of the 3D microstructure. Here, a sample is first scanned using synchrotron microtomography. After that, the same sample is subjected to serial sectioning. Light optical images are recorded every 10±2 micron of surface removal and EDX analysis is carried out after some intervals to identify the phases. Finally, the serial sectioning slices and the EDX analysis are correlated with the sXCT slices. The results allow to quantitatively describe the 3D microstructure of the piston alloys with an accurate identification of the present phases.