Starch consolidation of red clay-based ceramic slurry inside a pressure-cooking system

Abstract

The consolidation of red clay-based slurry by gelatinization of starch in a domestic pressure cooker was presented. Aqueous ceramic slurries were prepared consisting of a ternary powder mixture of red clay, quartz, feldspar, and different starch types. The starch slurries with and without the presence of ceramic particles demonstrated the same gelling mechanism and heating time inside the pressure cooker. The gel strengths of pressure-cooked samples were higher than samples heated conventionally. Subsequently, the shaping of large ceramic prototypes is possible using a calculated heating time based on best pressure cooking conditions. The physical characterizations disclosed that the pressure-cooked ceramic samples in dried and fired states exhibited better physical properties depending upon the type of starch added in the ceramic slurry. Specifically, the compressive strengths of fired ceramic bodies shaped in the pressure cooker ranged from 82 ± 2 to 255 ± 9 MPa with bulk porosities of 29.0 ± 0.8-18.7 ± 0.2%, whereas the conventionally shaped bodies possessed compressive strengths ranging from 138 ± 8 to 164 ± 11 MPa with bulk porosities of 25.6 ± 0.1-28.5 ± 0.2%.

Starch Consolidation Casting of Cordierite Precursor Mixtures—Rheological Behavior and Green Body Properties

“…2 Further applications of this processing technique, using either native or modified starches, concerned porous calcium carbonate, 3 silica, 4 gibbsite, 5 zirconia, 6 mullite, [7][8][9] , and even cermets 10 and metals (porous steels) prepared by the powder metallurgy route. 11 Also clay-based materials, 12,13 and, very recently, porcelain foams 14 have been prepared using starch consolidation casting. At the same time, processing details as well as process optimization and material characterization issues of starch consolidation casting were further investigated for alumina [15][16][17][18][19][20][21][22][23][24] and cordierite.…”

Starch consolidation of SiC ceramics: processing and low-temperature sintering in an air atmosphere

“…Depending on the processing technique selected, porosity content achieved, pore size distribution, and degree of pore interconnectivity factors which have direct effects on the properties of the porous ceramic are varied. Among the approaches taken in the recent focus on a novel processing of porous ceramics, the starch consolidation technique has attracted significant attention due to its near-net shaping capability without requiring specialized equipment, its ease of processing, and its cost-effectiveness [53][54][55][56][57][58][59][60][61][62][63][64][65][66][67][68][69]. Also, components from simple to complex shapes can be produced by this technique.…”

Potato starch consolidation of aqueous HA suspension

“…The main advantage of using starch as a consolidating agent for ceramic slurries compared to the other biopolymers and natural polysaccharides is back to its chemical purity that secures residual-free during starch burnout. In addition, it is economically cheap and environmental-friendly technology for implementation in ceramic processing to produce ceramic materials with various applications [17].…”