Polymer Bridging Induced by a Single Additive Imparts Easy-To-Implement Green Machinability to Yttria-Stabilized Zirconia

Cold isostatic pressing, gelcasting, and protein coagulation are the main methods to produce machinable green bodies of ceramics. They generally employ multiple additives, such as binders, dispersants, and coagulants, and require numerous steps to embody a green body that can withstand further shaping and machining. This study reports a method that forms a ceramic dough that can be manipulated by hand, cut, or pushed into a mold. This facile method relies on a single additive─a linear copolymer─to homogeneously coagulate yttria-stabilized zirconia through polymer bridging. The structure of the additive is systematically designed, and the amount to be used in the formulations is optimized through electrokinetic and rheological studies. The use of this additive at 1 wt % generates ceramic objects with ∼22% shrinkage and a density of 5.95 ± 0.02 g cm–3 after sintering and enables the fabrication of intricate shapes such as structures with triangle and hexagonal cavities via laser cutting and holes in high aspect ratio objects via conventional machining.