Configuration design and thermal conductivity of diamond-SiC/Al composites

Abstract

The preforms were prepared with SiC and W-coated diamond reinforcements, and the diamond-SiC/Al composites were prepared by gas pressure infiltration technology at 800 ℃ and 5 MPa. The properties of composite materials were analyzed by scanning electron microscope, infrared thermal imager and laser thermal conductivity meter. The influences of the content and the particle size ratio R of SiC and diamond on the configuration of composites were investigated to optimize the thermal conductivity of the composites. The results show that with the same SiC particle size, the thermal conductivity of the composites will be significantly improved with the increase of diamond volume fraction. When the volume fraction of diamond is 30%, the thermal conductivity of the composites containing F100 SiC is the best, which reaches 344 W/(m∙K). When the volume fraction of diamond is the same and the particle size ratio R increases from 0.07 to 0.65, the thermal conductivity of the composite increases in turn. Moreover, the thermal conductivity of composites with diamond volume fraction of 15% increases from 174 W/(m∙K) to 274 W/(m∙K), which achieves the largest increase of 57%.Therefore, by improving the content and the particle size ratio of reinforcements in the diamond-SiC/Al composites, the configuration of composites can be regulated to realize full potential of thermal conductivity.

Keywords

• diamond-sic/al composite
• gas pressure infiltration
• composite configuration
• thermal conductivity