The fabrication of Al–diamond composites for heat dissipation by liquid–solid separation technology

Low-cost and good quality Al–diamond composites were prepared in the application of heat dissipation using an advanced liquid–solid separation technology. Their thermal conductivity (TC) and coefficient of thermal expansion (CTE) were measured, especially on the effect of diamond particle surface metallization. The TC of composites reinforced with Ni-coated diamond particles was found to have increased by almost 80 % compared to that of Al alloys. The diamond surface in the composites was characterized using an electron microprobe, X-ray diffraction and SEM. It was found that high TC of the composites was obtained due to the generation of AlNi and AlNi phases at their interfaces between Al and diamond. In addition, the theoretical calculation for TC and CTE of the composites show the similar tendency with their experimental data.