An experimental investigation on damping and thermal behavior of AZ91 alloy based hybrid composites

SiCp-Grp/AZ91 magnesium alloy matrix based hybrid composites were synthesized by stir casting with particle size of both SiC and graphite particles being 27 µm. The each of the reinforcement contents was varied from 0 to 3 wt. % in steps of 1 wt. %. The experimental results disclose that the reinforcements show a significant influence on the damping capacities and thermal properties of the composites. Dynamic Mechanical Analyzer (DMA) was used to carry out the Damping tests on cantilever specimens over a temperature range from room temperature to 400°C. It was found that the damping capacity of the hybrid composites increased with increasing temperature and reinforcement content. It was observed that the CTE, thermal diffusivity, thermal conductivity and specific heat reduced considerably with the increase in the reinforcement. However when measured against temperature in the range of 100°C to 400°C, the CTE, conductivity and thermal diffusivity of the composites specimens increased with increase in temperature. However increase in CTE of the composites with rise in temperature was not significant.