Journal of Materials Science, Vol.29, No.22, 5975-5984, 1994
Factors Affecting the Damping Capacity of Cast Aluminum-Matrix Composites
The damping capacity of stir-cast aluminium-matrix composites containing graphite and silicon carbide particles, were studied using a cantilever beam specimen and an HP 5423A Structural Dynamics Analyser, Damping data were determined in the first mode of vibration. Aluminium-matrix composites containing 5-10 vol % graphite particles and 10 vol % silicon carbide particles were prepared by the stir-casting technique and die cast to obtain standard samples (6 mm x 25 mm 100 mm). Graphite particles were found to be more effective in enhancing the damping capacity of composites compared to silicon carbide particles. The damping capacity of composites increased with the volume percentage of graphite within the range studied. However, no notable improvements in damping capacity were observed by dispersion of silicon carbide in aluminium alloy. The results have been analysed in terms of the effect of size, shape, nature and volume fraction of particles on the damping capacity of the aluminium matrix particulate composites and compared with the damping capacity data available in the literature. The effects of frequency, strain amplitude, temperature and processing on damping capacity of the aluminium matrix composites are reviewed.
Keywords:ALLOYS