DEVELOPMENT OF MANUFACTURING PROCESS FOR HIGH PURITY ELECTRONIC CERAMICS

1962 ◽  
Author(s):  
J. H. Battle ◽  
Jr. Marino ◽  
Currier A. J. ◽  
E. W.
Keyword(s):  
High Purity ◽  
Manufacturing Process ◽  
Electronic Ceramics

Capacity of the manufacturing process of Flebogamma® DIF, a new human high purity intravenous immunoglobulin, to remove a TSE model-agent

Biologicals ◽  
2010 ◽  
Vol 38 (6) ◽  
pp. 670-674 ◽  
Author(s):  
José M. Diez ◽  
Santiago Caballero ◽  
Francisco Belda ◽  
Magdalena Otegui ◽  
Rodrigo Gajardo ◽  
...  
Keyword(s):  
Intravenous Immunoglobulin ◽  
High Purity ◽  
Manufacturing Process

Development and Testing of High Purity Alumina Ceramics for SOFC Stack Components

2010 ◽  
Author(s):  
Paolo R. Zafred ◽  
Shay L. Harrison ◽  
Jeffrey J. Bolebruch
Keyword(s):  
High Purity ◽  
Manufacturing Process ◽  
Low Cost ◽  
Slip Casting ◽  
Alumina Ceramic ◽  
High Alumina ◽  
Injection Molding Process ◽  
Development Effort ◽  
Alumina Ceramics ◽  
Molding Process

The successful attainment of many of the next generation Siemens SOFC Advanced Module features is dependent on development of key components required to provide fuel and process air to a stack of Delta cells. The overall objectives of this development effort included design and analysis of key stack components, fabrication of low cost net shape castings, characterization of high purity alumina ceramic material, and validation through full scale testing in Single and Multi-Cell Test Articles. The manufacturing process chosen for fabrication of stack components is a unique injection molding process referred to as the Blasch process. The Blasch process is a relatively low cost manufacturing process which allows for the fabrication of complex, close tolerance, near net shapes in a range of high alumina ceramic compositions without the need for expensive secondary machining. The Blasch process allows engineers to design virtually without restrictions related to other forming processes such as slip casting, extrusion, or pressing. The process utilizes nanotechnology to strongly bind together ceramic slurries containing one of a series of proprietary binders that can be activated by utilization of specific time/temperature processing. After casting into engineered molds, the binders in these slurries are caused to precipitate irreversibly and, upon firing, form a particularly thermal shock resistant ceramic bond containing no free silica. Ceramic shapes formed in this process shrink minimally and predictably, during firing, and therefore this is one of the few processes that can be claimed as true net shape manufacturing. Considerable effort went also in the development of a new class of failure tolerant alumina ceramics for SOFC stack components for service in reducing atmosphere at temperatures up to 1000°C. Pressureless infiltration of freeze cast alumina parts with chromium oxide was conducted to improve material’s strength. Strengthening of the porous alumina matrix is postulated to be a combination of both fracture toughness increase and crack size decrease, as a result of the infiltration process. Final results suggest that mechanical properties of infiltrated ceramics are superior to conventional porous freeze cast alumina material. This paper addresses the approach to ceramic castings design for SOFC stack components, the fabrication challenges with respect to shape complexity and the experimental tests performed to validate the material choice.

Molecularly Modified Alkoxide Precursors for Synthesis of Dielectric Ceramics.

1990 ◽  
Vol 180 ◽  
Author(s):  
Pradeep P. Phule ◽  
Farida Khairulla
Keyword(s):  
Chemical Synthesis ◽  
High Purity ◽  
Low Temperatures ◽  
Alkaline Ph ◽  
Ultrafine Powders ◽  
Chemical Polymerization ◽  
Electronic Ceramics ◽  
Precipitation Technique ◽  
Dielectric Ceramics ◽  
Alkoxide Precursors

ABSTRACT:Chemical synthesis of titanate and zirconate based multicomponent electronic ceramics using molecularly modified alkoxide precursors is discussed. Controlled chemical polymerization of the modified alkoxides was conducted to prepare multicomponent gels which on calcination at moderate temperatures (700 – 1000°C) formed high purity, ultrafine powders (e.g. BaTiO3, ZrTiO4, LiTaO3). In the sol-precipitation technique modified precursors were used to prepare ultrafine (< 100 nm) and crystalline powders of such ceramics as BaTiO3 and BaZrO3 at low temperatures (< 100°C), under highly alkaline (pH > 13) conditions.

Observations oh Nucleation and Growth of Voids in Nickel

1970 ◽  
Vol 28 ◽  
pp. 414-415
Author(s):  
J. L. Brimhall ◽  
H. E. Kissinger ◽  
B. Mastel
Keyword(s):  
High Purity ◽  
Growth Stage ◽  
Elevated Temperatures ◽  
Early Growth ◽  
Nucleation And Growth ◽  
Pure Nickel ◽  
Different Temperatures ◽  
Total Fluence ◽  
Neutron Exposure ◽  
Growth Of Voids

Some information on the size and density of voids that develop in several high purity metals and alloys during irradiation with neutrons at elevated temperatures has been reported as a function of irradiation parameters. An area of particular interest is the nucleation and early growth stage of voids. It is the purpose of this paper to describe the microstructure in high purity nickel after irradiation to a very low but constant neutron exposure at three different temperatures.Annealed specimens of 99-997% pure nickel in the form of foils 75μ thick were irradiated in a capsule to a total fluence of 2.2 × 1019 n/cm2 (E > 1.0 MeV). The capsule consisted of three temperature zones maintained by heaters and monitored by thermocouples at 350, 400, and 450°C, respectively. The temperature was automatically dropped to 60°C while the reactor was down.

Preparation and characterisation of vanadium pentoxide supported rhodium catalyst

1988 ◽  
Vol 46 ◽  
pp. 946-947
Author(s):  
A. Legrouri
Keyword(s):  
Aqueous Solution ◽  
Thermal Decomposition ◽  
Physicochemical Properties ◽  
Surface Area ◽  
Vanadium Pentoxide ◽  
High Purity ◽  
Gas Adsorption ◽  
Rhodium Catalyst ◽  
Optical Methods ◽  
Reducible Oxides

The industrial importance of metal catalysts supported on reducible oxides has stimulated considerable interest during the last few years. This presentation reports on the study of the physicochemical properties of metallic rhodium supported on vanadium pentoxide (Rh/V2O5). Electron optical methods, in conjunction with other techniques, were used to characterise the catalyst before its use in the hydrogenolysis of butane; a reaction for which Rh metal is known to be among the most active catalysts.V2O5 powder was prepared by thermal decomposition of high purity ammonium metavanadate in air at 400 °C for 2 hours. Previous studies of the microstructure of this compound, by HREM, SEM and gas adsorption, showed it to be non— porous with a very low surface area of 6m2/g3. The metal loading of the catalyst used was lwt%Rh on V2Q5. It was prepared by wet impregnating the support with an aqueous solution of RhCI3.3H2O.

High-purity Ge x-ray detectors: Sensitivity factors and usefulness

1990 ◽  
Vol 48 (2) ◽  
pp. 548-548
Author(s):  
E. B. Steel
Keyword(s):  
High Purity ◽  
High Energy ◽  
Quantitative Chemical Analysis ◽  
Detector Performance ◽  
X Ray ◽  
Detector Sensitivity ◽  
Specimen Holder ◽  
Many Instruments ◽  
Charge Resolution ◽  
Sensitivity Factors

High Purity Germanium (HPGe) x-ray detectors are now commercially available for the analytical electron microscope (AEM). The detectors have superior efficiency at high x-ray energies and superior resolution compared to traditional lithium-drifted silicon [Si(Li)] detectors. However, just as for the Si(Li), the use of the HPGe detectors requires the determination of sensitivity factors for the quantitative chemical analysis of specimens in the AEM. Detector performance, including incomplete charge, resolution, and durability has been compared to a first generation detector. Sensitivity factors for many elements with atomic numbers 10 through 92 have been determined at 100, 200, and 300 keV. This data is compared to Si(Li) detector sensitivity factors.The overall sensitivity and utility of high energy K-lines are reviewed and discussed. Many instruments have one or more high energy K-line backgrounds that will affect specific analytes. One detector-instrument-specimen holder combination had a consistent Pb K-line background while another had a W K-line background.

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