Particulate Science and Technology, Vol.36, No.3, 324-331, 2018
On the thermal conductivity of bimodal SiC/A356 composites fabricated via powder metallurgy route
The present study investigates the thermal conductivity of bimodal SiC particulate distribution in aluminum matrix composites fabricated via powder metallurgy route. The effects of the SiCp reinforcement size distribution and processing parameters such as sintering time and temperature on the thermal conductivity have been examined. The Box-Behnken experimental array was employed to identify the effects of selected variables on the thermal conductivity of the composite. A reasonable augmentation in the thermal conductivity was observed with an increase in sintering time and %volume fraction of fine SiC particulates. It has been demonstrated that the matrix doped with fine SiC particulates (37 mu m) occupied interstitial positions and formed continuous SiC-matrix network resulting in minimizing the micropores that contributed for good thermal conductivity, that is, 235W/mK. Scanning electron microscopy (SEM) and x-ray diffraction (XRD) were conducted to evaluate the microstructure architecture and interfacial phase formation.
Keywords:Metal matrix composites;reinforcement size distribution;sintering temperature;sintering time;thermal conductivity