Dresden 2009 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
MM: Fachverband Metall- und Materialphysik
MM 44: Quasicrystals II
MM 44.4: Vortrag
Donnerstag, 26. März 2009, 14:45–15:00, IFW B
Mechanical milling of single-phase Al-Cu-Fe quasicrystals — •S. Scudino1, F. Ali1, V.C. Srivastava2,3, N.K. Mukhopadhyay4, K.B. Surreddi1, M. Sakaliyska1, V. Uhlenwinkel3, and J. Eckert1,5 — 1IFW Dresden, Institut für Komplexe Materialien, Dresden, Germany — 2Metal extraction & Forming Division, National Metallurgical Laboratory, Jamshedpur, India — 3Institut für Werkstofftechnik, Universität Bremen, Bremen, Germany — 4Centre of Advanced Study, Department of Metallurgical Engineering, Banaras Hindu University, Varanasi, India — 5TU Dresden, Institut für Werkstoffwissenschaft, Dresden, Germany
The effect of milling intensity on the microstructure of spray-deposited Al62.5Cu25Fe12.5 quasicrystals has been investigated. The first stages of milling are characterized by a strong decrease of the grain size and by the introduction of lattice strain. This effect increases with increasing the milling time and in the material milled for longer time the quasicrystals transform into a nanoscale bcc phase. At this stage, the quasicrystals are no longer observable, indicating a complete transformation of the quasicrystals into the bcc phase. The hardness of the milled powders decrease with increasing the milling time, most likely as a consequence of the increased volume fraction of the bcc phase. Finally, the bcc phase formed during milling is metastable and transforms back to the quasicrystalline phase during the heat treatment, which suggests that a composite material with optimized mechanical properties can be produced by an appropriate thermo-mechanical treatment.