High-Temperature Stiffness and Damping Measurements to Monitor the Glassy Intergranular Phase in Liquid-Phase-Sintered Silicon Carbides |
| |
| Authors: | Gert Roebben Omer Van der Biest Diletta Sciti Alida Bellosi Corneliu Sarbu Tom Lauwagie |
| |
| Affiliation: | National Institute for Materials Physics, Bucharest-Magurele, Romania; Department of Metallurgy and Materials Engineering, K. U. Leuven, Belgium; CNR-IRTEC, Research Institute for Ceramics Technology, Faenza, Italy; Department of Mechanical Engineering, K. U. Leuven, Belgium |
| |
| Abstract: | Detailed stiffness and internal friction ( Q −1) versus temperature curves were obtained for liquid-phase-sintered silicon carbides using advanced resonant beam analysis up to 1400°C. As-sintered materials display a stable Q −1-peak near 1100°C, superimposed on an increasing background. The change of stiffness associated with the damping peak is quantitatively related to the amount of matter in pockets of the amorphous intergranular phase in which the refractory SiC matrix grains are embedded. The successful removal of the amorphous pockets by annealing at 1900°C is deduced from the disappearance of the damping peak and confirmed with transmission electron microscopy. |
| |
| Keywords: | |
|
|
