Effect of solid loading and aggregate size on the rheological behavior of PDMS/Calcium Carbonate suspensions

Using SiC particles and powder, the modified Si and α-Si3N4powder as the main raw material, Si3N4-SiC composite materials have been fabricated by gelcasting. The Si3N4-SiC suspension with 75vol% (volume fraction) solid loading exhibits shear thinning rheological behavior under a shear rate from 10 to 160s-1, which meets the requirement of the gelcasting process. The bulk density of the green bodies after solidification is 2.57 g·cm-3and the flexural strength 16 MPa, the green bodies have a dense and uniform structure. The bulk density and flexural strength of the Si3N4-SiC composites after nitriding are 2.67g·cm-3and 48 MPa respectively; the strength is higher than that of other industrial products without gelcasting. Well-developed intertwined fibrous Si3N4crystals grow on the surface of the SiC particles to form a tight microstructure in the Si3N4-SiC composites after firing.

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The Maximum Solid Loading and Viscosity Estimation of Ultra-Fine ZnO-Al2O3 Mixed Powders Aqueous Suspensions

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.512-515.1803 ◽

2012 ◽

Vol 512-515 ◽

pp. 1803-1806

Author(s):

Yi Hua Sun ◽

Chen Hui Li ◽

Wei Hao Xiong ◽

Ping Feng

Keyword(s):

Zinc Oxide ◽

Rheological Behavior ◽

Polyacrylic Acid ◽

Apparent Viscosity ◽

Aqueous Suspension ◽

Relative Viscosity ◽

Experimental Results ◽

Solid Loading ◽

Solids Loading ◽

Wide Range

The rheological behavior of sub-micron zinc oxide and alumina mixture powders aqueous suspension has been investigated over a wide range of volumetric solids loading (Ø = 0.2–0.55), in which polyacrylic acid (PAA) was used as a dispersant. The dependence of relative viscosity (ηr)–solids loading (Ø) determined experimentally was compared with models. The experimental results showed that the suspension apparent viscosity (η) reached a minimum as the dispersant addition reached 0.2 wt%, the viscosity increased with the solids loading and the rheological behavior of the suspension was content basically with the model proposed by Liu. From ηr–Ø relationship the maximum solid loading (Øm) was estimated to be 0.55, which was in accord with our experimental results.

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Rheological Behavior of Blends Gas-Water Atomized Stainless Steel Powder

Materials Science Forum ◽

10.4028/www.scientific.net/msf.727-728.239 ◽

2012 ◽

Vol 727-728 ◽

pp. 239-242

Author(s):

Suzy Pascoali ◽

Lucas Dominguini ◽

Joel Brasil Borges ◽

Paulo A.P. Wendhausen

Keyword(s):

Stainless Steel ◽

Rheological Behavior ◽

Particle Morphology ◽

Steel Powder ◽

High Viscosity ◽

Stainless Steel Powder ◽

Solid Loading ◽

Capillary Rheometry ◽

Rheological Analysis ◽

Solids Loading

This work evaluates the influence of particle morphology in mixture rheology. Range of particle morphology was used, changing in the mixtures the proportion of spherical powders and irregular powders, respectively gas and water atomized powders, in fraction of 0, 25, 50, 75 and 100% in mass. Components were obtained by mixtures with solid loading very close to critical values. Rheological analysis of the mixtures was elaborated in a capillary rheometry. The solids loading maximum was larger in 10% for the mixtures with only gas atomized powder, when compared to the mixture with just water atomized powder. The mixtures between gas and water atomized powders with maximum solid loading present difficulties in obtaining homogeneity and presents high viscosity.

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Rheological behavior of titania ink and mechanical properties of titania ceramic structures by 3D direct ink writing using high solid loading titania ceramic ink

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2018.12.334 ◽

2019 ◽

Vol 783 ◽

pp. 321-328 ◽

Cited By ~ 5

Author(s):

Tao Chen ◽

Aihua Sun ◽

Chengyi Chu ◽

Huansheng Wu ◽

Jiang Wang ◽

...

Keyword(s):

Mechanical Properties ◽

Rheological Behavior ◽

Solid Loading ◽

High Solid ◽

Direct Ink Writing ◽

High Solid Loading

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Study of Rheological Behavior of Calcium Carbonate Filled Polypropylene in Dynamic Extrusion

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1053.231 ◽

2014 ◽

Vol 1053 ◽

pp. 231-234 ◽

Cited By ~ 1

Author(s):

Quan Wang ◽

Xiao Sun ◽

Zheng Huan Wu

Keyword(s):

Calcium Carbonate ◽

Vibration Frequency ◽

Rheological Behavior ◽

Apparent Viscosity ◽

Polymer Melt ◽

Measuring Apparatus ◽

Melt Rheology ◽

Sinusoidal Vibration ◽

Dynamic Extrusion ◽

Vibration Parameters

A novel rheological measuring apparatus was designed, which introduced an additional sinusoidal vibration in parallel on the extruding direction of polymer melt in this paper. Melt rheology of polypropylene filled CaCO3 particles in various amounts of filler (i.e. with 3 and 20 wt%) during capillary melt-extrusion were investigated respectively. The effects of vibration parameters on rheological behaviors were studied. Compared with the steady extrusion, the apparent viscosity of filled system decreased remarkably with the increase of vibration frequency and amplitude. The apparent viscosity reached to the minimum value as vibration frequency was about 8 Hz. When the filled percentage of CaCO3 was low, the response of apparent viscosity will be more distinct with the increasing vibration parameters.

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