Paper number 925
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MMCS CHARACTERISATION BY INTERNAL FRICTION MEASUREMENT |
Irina SEVERIN1, Michelle SALVIA2, Gheorghe ZGURA2
1Department of Materials Technology & Welding, "Politehnica" University of Bucarest
313, Splaiul Independentei, cod 77206, Bucarest, Romania
2Laboratoire d'Ingénierie et Fonctionnalisation des Surfaces,
Département Matériaux-Mécanique Physique, Ecole Centrale de Lyon,
36, Avenue Guy de Collongue, 69131, Ecully Cedex, France
| Summary | The analysis of composites thermomechanical behaviour is complex considering that the deformation incompatibilities between matrix and reinforcements may be attenuated by different mechanisms. The internal friction and the transversal elastic modulus of an Al / SiCp composite have been measured using an experimental equipment based on sample's torsion loading in forced oscillation regime at low frequencies. The temperature was controlled and varied in the interval 90/500 K. Analysing the general aspect of the composite's internal friction spectrum, the peaks presence has been noticed. In the case of 6063 / SiCp composite has appeared a transitory phenomenon of internal damping characterised by a maximum centred on the temperature of 330 K, whose intensity increased with the heating rate and the oscillation period. The phenomenon, particular for composites, has been associated to the interface presence and the dislocation saturated non-deformable zone around the reinforcements. |
Keywords | metal matrix composites, damping, interface, dislocation, non-deformable zone. |