Additive manufacturing of zirconia parts with organic sacrificial supports

Abstract

Ceramic On‐Demand Extrusion (CODE) process has been recently proposed for additive manufacturing of strong ceramic components via extrusion. This paper focuses on fabricating 3 mol% yttria‐stabilized zirconia (3YSZ) components using CODE process, and enabling CODE to produce parts with support structures. A colloidal suspension of 3YSZ was developed and deposited through the main nozzle, and an organic feedstock was developed and deposited by means of another nozzle to fabricate supports. After printing and drying of raw parts, supports were removed by increasing the temperature and parts were then sintered to near theoretical (~99%) density. The maximum overhang angle that could be built with no support was also found out to be approximately 60 degrees. Three organic support materials, that is, polycaprolactone (PCL), silicone, and petrolatum were prepared and tested. PCL and petrolatum were identified as feasible support materials. Specimens were fabricated to validate the efficiency of the support materials and to evaluate CODE's capability for building parts with complex geometry. The microstructures of these parts were also analyzed via scanning electron microscopy.

A review of additive manufacturing technology and its application to foundry in China

“…To obtain complex (hollow, cantilever) ceramic components, double-extrusion and multiple-extrusion LEF methods were developed. Also, researchers have developed a variety of supporting materials for the forming of complex components, including salt base, calcium oxide base, graphite base, starch base, plastic base, etc., and prepared components with different levels of complexity, such as Mg scaffolds with well-controlled and ordered porosity, turbine blower ceramic shell, etc [112][113][114][115][116][117][118] . However, due to the intrinsic behaviors of the LEF process, deposited slurry filaments accumulate layer by layer, and the corresponding sample's surface inevitably exhibits "laminated striation" morphology (Fig.…”