Pore structure evolution during solvent extraction and wicking

2-D simulation of wick debinding for ceramic parts in close proximity

“…Vetter et al (1994) subsequently reported that German's model did not provide good agreement with experimental results and suggested an alternative binder removal mechanism that considered the binder leaving the part via distinct binder-rich and binder-lean zones. However, the experimental results reported by Bao and Evans (1991) and by Kim et al (1996) showed the binder to be distributed uniformly through the part, in contrast to both the above descriptions. These observations are consistent with capillary-driven flow through a porous medium, as described qualitatively by German and Bose (1997).…”

“…The evaporated binder or combustion products pass through large pores evacuated by wicking, so that the build-up of pressure in the part is reduced, mitigating the formation of defects (Kim et al, 1996). The heating cycle must be correctly specified so that evaporation does not take place too early, or later than necessary.…”

Partial wick-debinding of low-pressure powder injection-moulded ceramic parts

“…4,7 With more precise examinations of the binder removal rate it has been confirmed that wick-debinding must take place via more than a single mechanism. 6,10,11 One clearly observable effect is a rapid decrease in the binder content at the beginning of the process. This has been attributed to the pressure arising from the thermal expansion of the binder, 10 although the authors did not explain this effect in detail.…”

Water‐Soluble Binder System Based on Poly‐Methyl Methacrylate and Poly‐Ethylene Glycol for Injection Molding of Large‐Sized Ceramic Parts

“…For the dissolution and diffusion of the water‐soluble composition that are determined by many factors including temperature, ambient concentration, surface of the ceramic particles and the rest binders, it is difficult to set quantitative model for water debinding process. In Kim and Krauss's research, the parabolic relationship between the fraction of binder and debinding time was used, but the effects of the sample dimension were not considered . Lin and German set the linear relationship between the natural logarithm of the fraction of remaining binder and debinding time for solvent debinding.…”

“…In Kim and Krauss's research, the parabolic relationship between the fraction of binder and debinding time was used, but the effects of the sample dimension were not considered. 25,26 Lin and German set the linear relationship between the natural logarithm of the fraction of remaining binder and debinding time for solvent debinding. This relationship was still based on the samples of infinite geometry.…”