Binder Jetting of High Temperature and Thermally Conductive (Aluminum Nitride) Ceramic

This work reports on the novel fabrication of aluminum nitride (AlN) complex components using binder jetting, on the use of sintering and hot isostatic pressing (HIPing) to increase their density, and on the characterization of the printed material, including thermal conductivity. The HIPing parameters employed were a temperature of 1900 °C using a rich nitrogen atmosphere at a pressure of 30,000 psi during 8 h. Results show that the printed and HIPed AlN components had a 1.96 g/cm3 (60.12%) density when compared to theoretical values. The thermal conductivity for densified and HIPed components was measured in the range from 23 °C to 500 °C resulting in values from 4.82 W/mK to 3.17 W/mK, respectively. Characterization using scanning electron microscopy, energy dispersive X-ray spectroscopy and X-ray diffraction was used to investigate the ceramic structural morphology of the sintered and HIPed material, its chemical composition, and crystal structure of the binder jetting manufactured AlN components.