Wick Debinding - An Effective Way of Solving Problems in the Debinding Process of Powder Injection Molding

Abstract

Some Critical Issues for Injection Molding 90 1990) or wick-debinding. A wicking agent can be in the form of a porous solid substrate plate or in the form of a loose powder or granulate. The granular form offers a gentle physical support for samples, regardless of their shape, and thus prevents certain flaws, such as distortion and cracking. The capillary extraction is uniform over the entire surface of the green body, which ensures that debinded parts also have, as much as possible, a uniform structure after the wick-debinding. A solid plate does not offer so many benefits; however it has one advantage over the granular form of wicking agent, i.e., there are fewer practical problems when handling the compacts after the debinding. The wick-debinded parts do not have to be cleaned and are simply transferred to the sintering furnace.

Manufacturing complex Al2O3ceramic structures using consumer-grade fused deposition modelling printers

“…When the optimized debinding program is used, the exothermic peak can be reduced significantly and a more continuous loss of mass can be observed during the debinding stage, as shown in Figure 5(b). The optimized debinding program is characterized by slower heating rates and additional dwell times for a gentler binder removal, which mitigates the aforementioned formation of defects (Gorjan, 2012). The final mass loss of the samples was 19.0 Figure 5 I).…”

“…Partial debinding with a solvent or supercritical fluid can be used to avoid structural defects in the ceramic parts (Chartier et al, 1995). Alternatively, debinding in a powder bed (PB) can be used, where the capillary forces in action extract the liquid binder components and any decomposition products with a low viscosity from the part (Gorjan, 2012;Gorjan et al, 2015Gorjan et al, , 2017Trunec and Cihlar, 2002), a process also referred to as wicking.…”

Rheological Behavior of Zirconia Added Alumina Mixture

“…Thermal debinding was running at the temperature 550 °C and hold for 3 hours then continued with the heating up to 700 °C at the 0.5 °C/min in order to remove the binder palm stearin from the mold sample. A slow heating rate was applied based on Gorjan [10] who reported that the successful debinding process is commonly achieved by applying a very low heating rate. As a result, the binder decomposed gradually and the removed binder was eradicated and extracted to the surrounding embedment of alumina powder through the capillary forces.…”

Impact of Polymer Binders on the Structure of Highly Filled Zirconia Feedstocks

“…Debinding steps are then employed to extract the organic matrix, which constitutes 30 vol% to 60 vol% of the part. This processing step is critical and the selection of debinding routes has been extensively reviewed in the literature [ 8 , 9 , 10 ]. In order to favor shape retention, and to prevent defect creation, low molar mass binder is first removed via solvent extraction.…”