The effect of powder feedstock and heat treatment on the thermal and mechanical properties of binder jet printed ZrC

Abstract

Zirconium carbide (ZrC) disks were fabricated using binder jet printing to study the effect of powder feedstock, print parameters, and heat treatment on flowability and final materials properties. A median volumetric particle size smaller than 10 μm was shown to cause the powder to stop flowing during printing. Disks were printed using ZrC with suitable flowability and then heat-treated at temperatures between 1800 °C and 2200 °C for 1 or 5 h. The density, part shrinkage, thermal diffusivity, and fracture strength all increased with increasing temperature and time. The heat-treated disks were then heated to 2200 °C for 5 h and the properties converged for disks of the same particle size, indicating the hottest temperature and longest time of exposure dictates the final properties. Lastly, it was shown that larger particles produce lower density materials with worse thermal diffusivity, most likely because of poor connectivity between particles after heat treatment.