Composites studied here were processed by an original gas-pressure infiltration developed in our laboratory. The processed composites were based on aluminum or magnesium alloys reinforced with short Al2O3 fibers or long C or SiC fibers. Composites were submitted to thermal cycling. A large damping maximum and a modulus anomaly were observed at low temperature in the case of magnesium matrices. These features were interpreted as due to the motion of dislocations in the matrix, which are relaxing the interface thermal stresses.
Publications (2000-2009)
Chowdhury A S M F, Mari D, Schaller R, Thermal stress relaxation in magnesium matrix composites controlled by dislocation breakaway. Composites Science and Technology. In Press, Accepted Manuscript doi:10.1016/j.compscitech.2009.10.001
Chowdhury A S M F, Mari D, Schaller R, Analysis of transient mechanical loss due to thermal stresses in metal matrix composites. Materials Science and Engineering: A. 2009; 521-522, 310-313
A. S. M. F. Chowdhury D M, R. Schaller,, Thermal stress relaxation in magnesium matrix composites studied by mechanical spectroscopy. Phys. Stat. Sol. (a). 2008; 205, 249-254.
Schaller R, Mechanical spectroscopy of interface stress relaxation in metal-matrix composites. Materials Science and Engineering: A. 2006; 442, 423-428.
O. Couteau and R. Schaller, “Etude par spectroscopie mécanique de l’interface dans des composites à matrice magnésium.”, J. Phys. IV 106 , 63-68, (2003).
R. Schaller, “Metal matrix composites, a smart choice for high damping materials.”, J. Alloys and Compounds 355 , 131-135, (2003).
O. Couteau and R. Schaller, “Interface stress relaxation in magnesium matrix composites studied by mechanical spectroscopy.” Materials Science and Technology 19 , 955-958, (2003).
E. Carreño-Morelli, N. Chawla and R. Schaller, “Thermo-mechanical characterization of 2080 Al/SiCP composites by mechanical spectroscopy.”, J. of Materials Science Letters 20, 163-165, (2001).
E. Carreño-Morelli, “Interface stress relaxation in metal matrix composites”, in Mechanical Spectroscopy Q-1 2001, R. Schaller, G. Fantozzi and G. Gremaud, eds., Materials Science Forum, vol. 366-368, 570-580 (2001).
C.Y. Xie, E. Carreño-Morelli, R. Schaller, Y. Pitton and R.C. Fornerod, “Mechanical loss spectrum of aged Al-Mg-Si alloys.”, Phil. Mag. A 81 , 2149-2160, (2001).
R. Schaller, D. Vincent. “High damping capacity magnesium-silicon alloy – is esp. eutectic alloy, is used for light-constructional parts.Patent CH667674-A, (1988)