Hydrothermal-Assisted Transient Binder Jetting of Ceramics for Achieving High Green Density

Ceramic additive manufacturing (AM) provides a freeform fabrication method for creating complex ceramic structures that have been extremely difficult to build by traditional manufacturing processes. However, ceramic structures made by AM processes usually exhibit a relatively low density, which is largely due to the use of a large amount of organic binder in shaping green bodies. In this research, we present a new ceramic AM process, named hydrothermal-assisted transient binder jetting (HTBJ), which utilizes a water-based hydrothermal mechanism to fuse particles, eliminating the use of binders in forming green bodies. A prototype system for the proposed HTBJ process is introduced. The effects of process parameters (such as layer thickness, printing passes, prepressing and final pressing pressure, and temperature) on the properties of achieved green parts are investigated. Experimental results indicate that, with optimized process parameters, HTBJ can achieve three-dimensional ceramic green parts with a high density of up to 90%.