Dispersion, rheology and aqueous tape casting of alumina–zirconia composites

Abstract

Alumina and zirconia were dispersed individually in aqueous media using Darvan C as the dispersant and at optimised pH condition. Based on sedimentation, rheology, yield stress, electrodeposition and zeta potential measurements, 2 wt-% of the dispersant and a pH of 10 . 5 were found to be the optimum condition for the codispersion of alumina and zirconia. Aqueous tape casting slurries with a solid loading of 32 wt-% were prepared under the optimised conditions of dispersion. Alumina-zirconia (50 : 50) composite tapes of 40 mm thickness and 56% green density were obtained.

Defect free carbon tapes as thermal fugitives for multilayer ceramic application

“…30 The critical factors for a dispersant to be an effective steric dispersant are (i) well anchoring on to the particle surface (ii) effective layer thickness (iii) proper stretched confirmation so that the tail portion extends into the liquid which depends on the solvent compatibility. [14][15][16][17][18][19]22 The solubility parameter (d) of MFO is 17?5 MPa 1/2 which is close to that of Xyl (18 MPa 1/2 ) rather than to that of EtOH (26 MPa 1/2 ). MFO is not soluble in pure EtOH.…”

The tape casting process for manufacturing low‐temperature co‐fired ceramic green sheets: A review

“…Plasticizers affect the rheological properties of the casting slurry and provide the sheet with the appropriate plasticity and flexibility . Table displays the organic materials commonly used in tape casting slurries that are discussed in more detail below …”

“…The production efficiency is always a consideration for manufacturing processes. For efficiency, faster drying times are always preferred . However, if the green tape solvent dries too fast, it may affect tape quality.…”

“…14 Table 1 displays the organic materials commonly used in tape casting slurries that are discussed in more detail below. [22][23][24][25][26][27][28]…”

“…For efficiency, faster drying times are always preferred. 23 However, if the green tape solvent dries too fast, it may affect tape quality. For example, pure ethyl acetate dries quickly, allowing for good production efficiency, but premature drying creates a skin over the green sheet.…”