Organic Additives and Ceramic Processing

Shanefield, Daniel J.

doi:10.1007/978-1-4757-6103-0

Cited by 64 publications

(62 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…It must be low enough to avoid the unwanted formation of aggregates 30,31 but high enough to favor the sintering of the material. The surface area of 55S-700 and 55S-800 materials were too high [ Fig.…”

Section: Resultsmentioning

confidence: 99%

Bioactive glass as precursor of designed‐architecture scaffolds for tissue engineering

Padilla

Sánchez‐Salcedo

Vallet‐Regí

2006

J Biomedical Materials Res

View full text Add to dashboard Cite

In this work, the conditions to obtain concentrated and fluid suspensions from a bioactive glass (55-SiO(2); 41-CaO; 4-P(2)O(5); mol %) were investigated. The influence of the heat treatment of the glass on the specific surface area, solubility, bioactivity, and finally on their dispersion characteristics was studied. Zeta potential and viscosity measurements were carried out, and based on the obtained results, the best dispersant was selected. The optimum concentration of dispersant, maximum content of solid and time of mixing were also investigated. Slurries containing 50 vol % could be obtained calcining the glass at 1100 degrees C and using Darvan 811 (sodium polyacrylate) as dispersant. Scaffolds with designed architecture were prepared from these suspensions combining the gelcasting method and the stereolithography technique. A polymeric negative (replica of the desired structure) was previously obtained by stereolithography. The slurry was cast into the molds and then polymerized (gelcasting method). The negative was eliminated by heat treatment. After sintering at 1300 degrees C, scaffolds with interconnected porosity and three-dimensional channels of 400-470 microm and macropores of 1.4 microm were obtained.

show abstract

Section: Resultsmentioning

confidence: 99%

Bioactive glass as precursor of designed‐architecture scaffolds for tissue engineering

Padilla

Sánchez‐Salcedo

Vallet‐Regí

2006

J Biomedical Materials Res

View full text Add to dashboard Cite

show abstract

“…[23] to be those with diameters between approximately 20 and 200 A Ê . Good precursors for ceramics and superconductors have surface areas of about 10 m 2 /g [20]. In this case the balance between obtaining a high surface energy for promotion of sintering, and a particle distribution that packs well is often optimal.…”

Section: Particle Sizementioning

confidence: 98%

“…A1 has a much wider size distribution than the other powders. All the B powders reveal a size distribution that is typical for commercial powders used to manufacture high performance ceramics [20]. The ratio of sizes in the commercial powder is very dierent from close packed.…”

Section: Particle Sizementioning

confidence: 99%

Surface chemistry of lanthanum chromite I. Multivariate data modelling of Brunauer-Emmett-Teller surface area by the use of particle size distribution data from photon-correlation spectroscopy measurements

Stakkestad

Sjöblom

Grung

et al. 1999

Colloid & Polymer Science

View full text Add to dashboard Cite

IntroductionThe interconnect is a critical component in a planar solid oxide fuel cell (SOFC) since, in addition to acting as the electrical connection between individual cells in series, it must also be gas tight in order to prevent mixing of the fuel and oxidizer. Doped lanthanum chromites exhibit the required phase stability, high electronic conductivity, and low ionic conductivity in both reducing and oxidizing environments making them suitable as interconnects at high temperatures (1000°C). Additionally, these materials are chemically compatible with the other fuel cell components [1]. Some independent studies reveal, however, that lanthanum chromite expands in a reducing atmosphere [2±5], at oxygen partial pressures well within the eective operating range of an SOFC. Doping with aliovalent B-site additives reduces the lattice expansion signi®cantly [6]. The lanthanum chromite powders that we have chosen to characterize contain the traditional Ca and Sr acceptor dopants, Ni and Zn dopants, and some double dopants (Sr with Ni, Cu, and Mg).In our previous publications [7,8] we reported on the electrical conductivity, microstructure, and mechanical properties of Ca-and Sr-doped LaCrO 3 interconnects for SOFO. Relative density, secondary phases, and grain boundary layers were found to have an impact on the electrical conductivity and the mechanical strength of these materials.Production of gas-tight, defect-free interconnects for SOFC is important regarding electrical output and lifetime. Defect-free ceramic composites with ®ne grain microstructures can be obtained by the processing of colloidal particles [9]. During the mixing, dispersing, forming, and ®ring steps good colloidal control and hence knowledge of the surface chemistry of the components is important. Sintering of the green body to maximum density depends on the surface free energy available in the powder, and the particle packing eciency.Hence, important characterization of the ceramic powders is by the Brunauer-Emmett-Teller (BET) surface area, and by the particle size distribution. Knowledge about the surface properties also gives guidelines Abstract Particle size distributions, measured by photon-correlation spectroscopy and Brunauer-EmmettTeller (BET) surface areas, were determined for several lanthanum chromite powders with dierent dopants. Principal component analysis (PCA) was used to reveal similarities among the dierent powders with regard to the input variables particle size, BET surface area, and calcination temperature. Correlation among the variables was also easily revealed by PCA. Partial-least-squares multivariate-response modelling was used to calibrate the BET surface area from particle size data and calcination temperatures. A model explaining 93% of the variance in the data, with good predictive power, was developed. The model revealed that the content of smallest-sized particles and the calcination temperature were important parameters in the prediction of the BET surface area.

show abstract

“…Deagglomeration was achieved by sonication ( Figure 5) in an appropriate solvent. 7,8 for about 1-10 minutes. It was expected that the silicon nanoparticles then would collect around the surface of the larger particles (in this case, the graphite).…”

Section: Task 1 Cvd-assisted Syntheses Of Graphite/silicon/carbon Comentioning

confidence: 99%

Composit, Nanoparticle-Based Anode material for Li-ion Batteries Applied in Hybrid Electric (HEV's)

Gulbinska¹

2009

View full text Add to dashboard Cite

Organic Additives and Ceramic Processing

Cited by 64 publications

References 0 publications

Bioactive glass as precursor of designed‐architecture scaffolds for tissue engineering

Bioactive glass as precursor of designed‐architecture scaffolds for tissue engineering

Surface chemistry of lanthanum chromite I. Multivariate data modelling of Brunauer-Emmett-Teller surface area by the use of particle size distribution data from photon-correlation spectroscopy measurements

Composit, Nanoparticle-Based Anode material for Li-ion Batteries Applied in Hybrid Electric (HEV's)

Contact Info

Product

Resources

About