Metallurgy, Vol. 44 No. 4, 2005.
Original scientific paper
Superplastic Deformation of Al-Al4C3 Composites
M. Besterci
O. Velgosová
F. Lofaj
L. Kováč
Abstract
Deformation of the Al-Al4C3 composites with different volume fraction of Al-Al4C3 phase was investigated at different temperatures (293 - 723 K) and different strain rates (2,5 * 10-5 s-1 do 1,0 * 10-1 s-1). At temperatures 673 - 723 K and at the highest strain rate of 1,0 * 10-1 s-1, a significant ductility increase was observed. TEM analysis suggests the onset of superplasticity may be the result of dynamic grain polygonization, grain slip and rotation, partial recrystallization and dislocation creep in the tested system, which is known as strain induced dynamic recovery. Increase of the volume fraction of secondary phase in the studied composite resulted in a shift from slip on grain boundaries controlled mechanism to the grain rotation controlled deformation mechanism.
Keywords
composite material; deformation; strain rate; TEM; superplasticity
Hrčak ID:
127820
URI
Publication date:
1.10.2005.
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