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G. Requena, H.P. Degischer, E. Marks, E. Boller:
"Evolution of the 3D Microstructure of a short fibre reinforced Al-Si alloy during creep";
Talk: 16th International Conference on Composite Materials, Kyoto/ Japan; 07-08-2007 - 07-13-2007; in: "Proceedings of the 16th International Conference on Composite Materials", (2007), 1 - 10.

The evolution of the microstructure during creep of an AlSi12CuMgNi alloy with 15 vol% of Al2O3 short fibres is investigated by means of synchrotron micro-tomography. The results reveal a change of the morphology of the hybrid reinforcement composed by the eutectic-Si, the short fibres and the intermetallic particles. This change takes place due to the diffusion induced spheroidisation and coarsening of Si and of the intermetallic particles. The interconnectivity of the hybrid reinforcement increases during long-term creep exposure reaching almost full connectivity after 6400 h of creep.
The analysis of creep damage during secondary creep stage shows the increase of the void volume fraction by a factor of 2, while the number of voids per volume remains practically constant. An analysis of the voids´ location indicates that pores generated during the processing of the composite grow and no new pores are produced during the primary and secondary creep stage.

micro-tomography, short fibre reinforced metals, creep, hybrid reinforcement