Three-dimensional printing of abrasive, hard, and thermally conductive synthetic microdiamond-polymer composite using low-cost fused deposition modeling printer
Waheed, S and Cabot, JM and Smejkal, P and Farajikhah, S and Sayyar, S and Innis, PC and Beirne, S and Barnsley, G and Lewis, TW and Breadmore, MC and Paull, B, Three-dimensional printing of abrasive, hard, and thermally conductive synthetic microdiamond-polymer composite using low-cost fused deposition modeling printer, ACS Applied Materials and Interfaces, 11, (4) pp. 4353-4363. ISSN 1944-8244 (2019) [Refereed Article]
A relative lack of printable materials with tailored functional properties limits the applicability of three-dimensional (3D) printing. In this work, a diamond–acrylonitrile butadiene styrene (ABS) composite filament for use in 3D printing was created through incorporation of high-pressure and high-temperature (HPHT) synthetic microdiamonds as a filler. Homogenously distributed diamond composite filaments, containing either 37.5 or 60 wt % microdiamonds, were formed through preblending the diamond powder with ABS, followed by subsequent multiple fiber extrusions. The thermal conductivity of the ABS base material increased from 0.17 to 0.94 W/(m·K), more than five-fold following incorporation of the microdiamonds. The elastic modulus for the 60 wt % microdiamond containing composite material increased by 41.9% with respect to pure ABS, from 1050 to 1490 MPa. The hydrophilicity also increased by 32%. A low-cost fused deposition modeling printer was customized to handle the highly abrasive composite filament by replacing the conventional (stainless-steel) filament feeding gear with a harder titanium gear. To demonstrate improved thermal performance of 3D printed devices using the new composite filament, a number of composite heat sinks were printed and characterized. Heat dissipation measurements demonstrated that 3D printed heat sinks containing 60 wt % diamond increased the thermal dissipation by 42%.