Rheological properties of re-melted paraffin-wax suspensions used for LPIM

Influence of dispersant, storage time and temperature on the rheological properties of zirconia–paraffin feedstocks for LPIM

“…7), which is in agreement with a recent study by Dakskobler and Kosmac. 7 Regarding the viscosity, a comparable behaviour could be observed, as shown in Fig. 8 that depicts the behaviour for the shear rate 10 s −1 .…”

“…11), which is in conformity with other studies. 7,17 For instance, the yield point decreases from 709.2 Pa (50 vol%) to 268.4 Pa (47.5 vol%) and to 107.0 Pa (45 vol.%) at 70 • C working temperature. The viscosity behaves analogically, e.g., η decreases from 21.03 Pa s (50 vol%) to 10.4 Pa s (47.5 vol%) and 5.3 Pa s (45 vol%) for a shear rate of 100 s −1 at 70 • C. As a result, the working temperature can be adjusted depending on the solids loading and can be chosen lower for feedstocks with lower solids loadings.…”

“…7 Thus, the yield stress prevents sedimentation and phase separation in the suspension. The influence of the amount of dispersant on viscosity and yield stress is considerable.…”

New eco-friendly binder based on natural rubber for ceramic injection molding process

“…According Khakbiz et al [16] this phenomenon discards the possibility of powder-binder separation during molding. For PIM process the Bingham or pseudoplastic rheological behavior is desired [17]. The effect of shear rate on viscosity is stronger for the feedstock 33BN/67PW, which sharply decreases viscosity whilst shear rate increases.…”

“…High values of yield stress would cause incomplete or problems with filling of suspension during injection, the suspension fills the mold like a thread of ribbon that coils upon itself (jetting), and induces the entrapment of air into moldings, generating mechanical stress. On the other hand, the absence of yield stress causes deformation during binder removal [1] due to weak strength of the particles network [17].…”