Loic Constantin’s paper accepted in Manufacturing letters, March 2020 “Additive manufacturing of copper/diamond composites for thermal management applications”
April 22, 2020
Copper (Cu)/diamond (D) composites have been extensively studied as the next-generation thermal management materials due to its excellent thermal property. However, the presence of D particles makes processing these composites difficult. Additive manufacturing (AM) provides an intriguing method to overcome this issue because of its high degree of freedom to fabricate complex shapes. In this letter, we demonstrated the feasibility to additively manufacture structures using Cu/D composite materials by laser directed energy deposition (LDED). D particles were coated with a graded TiO2-TiC interphase using a molten salt process to enhance its wettability with molten Cu. A relatively dense Cu/coated-D composite was printed (96%) at an optimized energy density of about 1250 J/mm3 (i.e., Power = 950 W, scan = 12.7, hatch = 0.3 mm and layer = 0.2 mm). Strong bonding between the matrix and reinforcement was observed, leading to a highly thermally conductive Cu/ 25 vol.% D composite (330 W/m.K). Furthermore, no graphitization of the D particles was observed after being exposed to the high laser power, thus making AM a suitable approach to manufacturing Cu/D composites.