Pressure infiltrated Cu/diamond composites for LED applications

Diamond reinforced copper (Cu/diamond) composites were prepared by a pressure infiltration technique. The composites show a super high conductivity of 713 W·m⁻¹·K⁻¹ in combination with an extremely low coefficient of thermal expansion (CTE) of 7.72 × 10⁻⁶ K⁻¹ (25–100°C), which are achieved by modifying the copper matrix with adding 0.3 wt.% of boron to get a good thermal contact between the matrix and the diamond particles. By adopting a series of postmachining techniques the composites were made into near-net-shape parts, and an electroless silver coating was also successfully plated on the composites. Finally, their potential applications in the thermal management of light emitting diodes (LED) were illustrated via prototype examples.