Effect of Surface Modification on Slip Casting of SiC Slurry

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.364.799 ◽

2013 ◽

Vol 364 ◽

pp. 799-803

Author(s):

Cai Hua Zheng ◽

Xiao Li Ji

Keyword(s):

Surface Modification ◽

Zeta Potential ◽

Slip Casting ◽

Solid Loading ◽

Low Viscosity ◽

Effect Of Surface

In this study,the Zeta potential of original and modified SiC micropowder was researched,and the effects of surface modification on SiC slurry solid loading,rheologyh and density of slip casting body were studied.The structure of body was looked through SEM. The results indicated that the dispersion of modified SiC micropowder was greatly improved,the slip casting SiC slurry which had 73vol% solid loading,low viscosity and good fluidity was prepared,after slip casting,the density of body was 2.698[g·cm-3],and the structure was uniform.

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ZTA Pipes with a Gradient Structure–Effect of the Rheological the Behavior of Ceramic Suspensions on the Gradient Structure and Characterized of the Obtained Products

Materials ◽

10.3390/ma14237348 ◽

2021 ◽

Vol 14 (23) ◽

pp. 7348

Author(s):

Radosław Żurowski ◽

Justyna Zygmuntowicz ◽

Paulina Piotrkiewicz ◽

Marcin Wachowski ◽

Michał M. Szczypiński

Keyword(s):

Rheological Properties ◽

Slip Casting ◽

Extreme Temperature ◽

Total Solid ◽

Solid Loading ◽

Gradient Structure ◽

Phase Gradient ◽

Low Viscosity ◽

Ceramic Suspensions ◽

Composite Pipes

This paper focuses on the verifying the possibility of producing Al2O3-ZrO2 composite pipes with a gradient structure using centrifugal slip casting method. The aim of the research is to define the correlation between the rheological properties of aqueous suspensions of ceramic powders with different solid loading and obtaining the ZrO2 phase gradient in the Al2O3 matrix. Such products, due to their unique properties, can be utilized in the transport of aggressive substances, even in extreme temperature or corrosive conditions. The suspensions and the sintered samples were characterized by: broad rheological analysis, scanning electron microscopy, X-ray diffraction, stereological analysis and Vickers hardness tests. The study reports on a series of samples produced of ceramic suspensions (70 vol.% Al2O3–30 vol.% ZrO2) differing in the total solid loading in the range of 30–55 vol.%. The results clearly indicate that obtaining the gradient structure of ceramic-ceramic composite pipes is closely related to the rheological properties of the suspensions from which the samples are cast. The phase gradient is obtainable from suspensions 30–40 vol.%, in which the possibility of moving ZrO2 particles relative to the Al2O3 is quite high—these suspensions are characterized by low viscosity and the dominance of viscous over elastic properties (G′ > G″).

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Effect of Surface Modification with TiO2 Coating on Improving Filtration Efficiency of Whisker-Hydroxyapatite (HAp) Membrane

Coatings ◽

10.3390/coatings10070670 ◽

2020 ◽

Vol 10 (7) ◽

pp. 670

Author(s):

Chenning Zhang ◽

Tetsuo Uchikoshi ◽

Lihong Liu ◽

Masanori Kikuchi ◽

Izumi Ichinose

Keyword(s):

Surface Modification ◽

Hydrothermal Synthesis ◽

Zeta Potential ◽

Au Nanoparticles ◽

Particle Growth ◽

Filtration Efficiency ◽

Tio2 Coating ◽

Free Standing ◽

Positively Charged ◽

Effect Of Surface

Whisker-like hydroxyapatite (HAp) particles were prepared by controlling particle growth via hydrothermal synthesis. The surface modification for the hydrothermally synthesized HAp whiskers was accomplished by TiO2 coating. After the TiO2 modification, the zeta potential of the HAp whiskers was significantly improved from +8.6 to +21 mV at pH = 8.5. A free-standing membrane (diameter of ~4.5 cm and thickness of ~0.2 mm) was fabricated by using the TiO2-coated HAp whiskers and was used to separate the Au nanoparticles (size = 5 nm and zeta potential = −38.6 mV at pH = 8.5) at a significantly high filtration efficiency of ~100%. The achieved high filtration efficiency was considered to be the result of effectively utilizing the electrostatic interaction between the positively-charged TiO2-coated HAp whiskers and negatively-charged Au nanoparticles. The excellently biocompatible and highly effective TiO2-coated HAp membrane would be potentially applied as biological and artificial separators in biotechnology processes for the biomedicine field.

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