@misc{MuellerKupschLaquaietal.2018, author = {M{\"u}ller, Bernd Randolf and Kupsch, Andreas and Laquai, Rene and Nellesen, Jens and Tillmann, Wolfgang and Kasperovich, Galina and Bruno, Giovanni}, title = {Microstructure Characterisation of Advanced Materials via 2D and 3D X-Ray Refraction Techniques}, series = {Materials Science Forum}, volume = {941}, journal = {Materials Science Forum}, publisher = {Trans Tech Publications Ltd}, address = {Zurich}, isbn = {978-3-0357-1208-7}, issn = {0255-5476}, doi = {10.4028/www.scientific.net/MSF.941.2401}, pages = {2401 -- 2406}, year = {2018}, abstract = {3D imaging techniques have an enormous potential to understand the microstructure, its evolution, and its link to mechanical, thermal, and transport properties. In this conference paper we report the use of a powerful, yet not so wide-spread, set of X-ray techniques based on refraction effects. X-ray refraction allows determining internal specific surface (surface per unit volume) in a non-destructive fashion, position and orientation sensitive, and with a nanometric detectability. We demonstrate showcases of ceramics and composite materials, where microstructural parameters could be achieved in a way unrivalled even by high-resolution techniques such as electron microscopy or computed tomography. We present in situ analysis of the damage evolution in an Al/Al2O3 metal matrix composite during tensile load and the identification of void formation (different kinds of defects, particularly unsintered powder hidden in pores, and small inhomogeneity's like cracks) in Ti64 parts produced by selective laser melting using synchrotron X-ray refraction radiography and tomography.}, language = {en} } @article{CabezaMuellerPereyraetal.2018, author = {Cabeza, Sandra and M{\"u}ller, Bernd R. and Pereyra, Ricio and Fernandez, Ricardo and Gonzalez-Doncel, Gaspar and Bruno, Giovanni}, title = {Evidence of damage evolution during creep of Al-Mg alloy using synchrotron X-ray refraction}, series = {Journal of applied crystallography}, volume = {51}, journal = {Journal of applied crystallography}, publisher = {International Union of Crystallography}, address = {Chester}, issn = {1600-5767}, doi = {10.1107/S1600576718001449}, pages = {420 -- 427}, year = {2018}, abstract = {In order to provide further evidence of damage mechanisms predicted by the recent solid-state transformation creep (SSTC) model, direct observation of damage accumulation during creep of Al-3.85Mg was made using synchrotron X-ray refraction. X-ray refraction techniques detect the internal specific surface (i.e. surface per unit volume) on a length scale comparable to the specimen size, but with microscopic sensitivity. A significant rise in the internal specific surface with increasing creep time was observed, providing evidence for the creation of a fine grain substructure, as predicted by the SSTC model. This substructure was also observed by scanning electron microscopy.}, language = {en} }