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Macro-meso-microsystems integration in LTCC : LDRD report.

Description: Low Temperature Cofired Ceramic (LTCC) has proven to be an enabling medium for microsystem technologies, because of its desirable electrical, physical, and chemical properties coupled with its capability for rapid prototyping and scalable manufacturing of components. LTCC is viewed as an extension of hybrid microcircuits, and in that function it enables development, testing, and deployment of silicon microsystems. However, its versatility has allowed it to succeed as a microsystem medium in its… more
Date: March 1, 2007
Creator: De Smet, Dennis J.; Nordquist, Christopher Daniel; Turner, Timothy Shawn; Rohrer, Brandon Robinson; Walker, Charles A.; Ho, Clifford K.. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Revolutionary systems for catalytic combustion and diesel catalytic particulate traps.

Description: This report is a summary of an LDRD project completed for the development of materials and structures conducive to advancing the state of the art for catalyst supports and diesel particulate traps. An ancillary development for bio-medical bone scaffolding was also realized. Traditionally, a low-pressure drop catalyst support, such as a ceramic honeycomb monolith, is used for catalytic reactions that require high flow rates of gases at high-temperatures. A drawback to the traditional honeycomb m… more
Date: December 1, 2004
Creator: Stuecker, John Nicholas; Witze, Peter O.; Ferrizz, Robert Matthew; Cesarano, Joseph, III & Miller, James Edward
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Fabrication of large-volume, low-cost ceramic lanthanum halide scintillators for gamma ray detection : final report for DHS/DNDO/TRDD project TA-01-SL01.

Description: This project uses advanced ceramic processes to fabricate large, optical-quality, polycrystalline lanthanum halide scintillators to replace small single crystals produced by the conventional Bridgman growth method. The new approach not only removes the size constraint imposed by the growth method, but also offers the potential advantages of both reducing manufacturing cost and increasing production rate. The project goal is to fabricate dense lanthanum halide ceramics with a preferred crystal o… more
Date: October 1, 2008
Creator: Boyle, Timothy J.; Ottley, Leigh Anna M.; Yang, Pin; Chen, Ching-Fong; Sanchez, Margaret R. & Bell, Nelson Simmons
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Near net shape forming processes for chemically prepared zinc oxide varistors.

Description: Chemically prepared zinc oxide powders are fabricated for the production of high aspect ratio varistor components. Colloidal processing in water was performed to reduce agglomerates to primary particles, form a high solids loading slurry, and prevent dopant migration. The milled and dispersed powder exhibited a viscoelastic to elastic behavioral transition at a volume loading of 43-46%. The origin of this transition was studied using acoustic spectroscopy, zeta potential measurements and oscill… more
Date: January 1, 2005
Creator: Lockwood, Steven John; Voigt, James A.; Tuttle, Bruce Andrew & Bell, Nelson Simmons
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

An analysis of the pull strength behaviors of fine-pitch, flip chip solder interconnections using a Au-Pt-Pd thick film conductor on Low-Temperature, Co-fired Ceramic (LTCC) substrates.

Description: The assembly of the BDYE detector requires the attachment of sixteen silicon (Si) processor dice (eight on the top side; eight on the bottom side) onto a low-temperature, co-fired ceramic (LTCC) substrate using 63Sn-37Pb (wt.%, Sn-Pb) in a double-reflow soldering process (nitrogen). There are 132 solder joints per die. The bond pads were gold-platinum-palladium (71Au-26Pt-3Pd, wt.%) thick film layers fired onto the LTCC in a post-process sequence. The pull strength and failure modes provided th… more
Date: September 1, 2008
Creator: Uribe, Fernando R.; Kilgo, Alice C.; Grazier, John Mark; Vianco, Paul Thomas; Zender, Gary L.; Hlava, Paul Frank et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Investigation of the effects of intense pulsed particle beams on the durability of metal-to-plastic interfaces.

Description: We have investigated the potential for intense particle beam surface modification to improve the mechanical properties of materials commonly used in the human body for contact surfaces in, for example, hip and knee implants. The materials studied include Ultra-High Molecular Weight Polyethylene (UHMWPE), Ti-6Al-4Al (titanium alloy), and Co-Cr-Mo alloy. Samples in flat form were exposed to both ion and electron beams (UHMWPE), and to ion beam treatment (metals). Post-analysis indicated a degrada… more
Date: February 1, 2005
Creator: Prasad, Somuri V.; Renk, Timothy J.; Provencio, Paula Polyak; Petersen, Donald W. (University of Alabama, Birmingham, AL); Petersen, Thomas D. (University of California, San Diego, CA); Buchheit, Thomas Edward et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

A micromechanical basis for partitioning the evolution of grainbridging in brittle materials

Description: A micromechanical model is developed for grain bridging inmonolithic ceramics. Specifically, bridge formation of a single,non-equiaxed grain spanning adjacent grains is addressed. A cohesive zoneframework enables crack initiation and propagation along grainboundaries. The evolution of the bridge is investigated through avariance in both grain angle and aspect ratio. We propose that thebridging process can be partitioned into five distinct regimes ofresistance: propagate, kink, arrest, stall, an… more
Date: October 9, 2006
Creator: Foulk, J. W., III; Cannon, R. M.; Johnson, G. C.; Klein, P. A. & Ritchie, R. O.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

NGNP Composites R&D Technical Issues Study

Description: This study identifies potential applications and design requirements for ceramic materials (CMs) and ceramic composite materials (CCMs) in the NGNP hightemperature gas-cooled reactor (HTGR) primary circuit. Components anticipated for fabrication from non-graphite CMs and CCMs are identified along with recommended normal and off-normal operating conditions. The evaluation defines required dimensions and material properties of the candidate materials for normal operating conditions (NOC), anticip… more
Date: September 1, 2008
Creator: Services, AREVA Federal
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Thermomechanical measurements on thermal microactuators.

Description: Due to the coupling of thermal and mechanical behaviors at small scales, a Campaign 6 project was created to investigate thermomechanical phenomena in microsystems. This report documents experimental measurements conducted under the auspices of this project. Since thermal and mechanical measurements for thermal microactuators were not available for a single microactuator design, a comprehensive suite of thermal and mechanical experimental data was taken and compiled for model validation purpose… more
Date: January 1, 2009
Creator: Baker, Michael Sean; Epp, David S.; Serrano, Justin Raymond; Gorby, Allen D. & Phinney, Leslie Mary
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Investigation of temporal contrast effects in femtosecond pulse laser micromachining of metals.

Description: Femtosecond pulse laser drilling has evolved to become a preferred process for selective (maskless) micromachining in a variety of materials, including metals, polymers, semiconductors, ceramics, and living tissue. Manufacturers of state-of-the-art femtosecond laser systems advertise the inherent advantage of micromachining with ultra short pulses: the absence of a heat affected zone. In the ideal case, this leads to micro and nano scale features without distortion due to melt or recast. Howeve… more
Date: June 1, 2006
Creator: Campbell, Benjamin (Pennsylvania State University, Freeport, PA) & Palmer, Jeremy Andrew
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Ultra high temperature ceramics for hypersonic vehicle applications.

Description: HfB{sub 2} and ZrB{sub 2} are of interest for thermal protection materials because of favorable thermal stability, mechanical properties, and oxidation resistance. We have made dense diboride ceramics with 2 to 20 % SiC by hot pressing at 2000 C and 5000 psi. High-resolution transmission electron microscopy (TEM) shows very thin grain boundary phases that suggest liquid phase sintering. Fracture toughness measurements give RT values of 4 to 6 MPam{sup 1/2}. Four-pt flexure strengths measured in… more
Date: January 1, 2006
Creator: Tandon, Rajan; Dumm, Hans Peter; Corral, Erica L.; Loehman, Ronald E. & Kotula, Paul Gabriel
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Tunable ionic-conductivity of collapsed Sandia octahedral molecular sieves (SOMS).

Description: This proposal focuses on the synthesis and characterization of ''tunable'' perovskite ceramics with resulting controlled strength and temperature of dielectric constants and/or with ionic conductivity. Traditional methods of synthesis involve high temperature oxide mixing and baking. We developed a new methodology of synthesis involving the (1) low temperature hydrothermal synthesis of metastable porous phases with ''tuned'' stoichiometry, and element types, and then (2) low temperature heat tr… more
Date: November 1, 2006
Creator: Pless, Jason; Nenoff, Tina Maria; Garino, Terry J. & Axness, Marlene
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Atomistic simulations of brittle crack growth.

Description: Ceramic materials such as lead zirconium titanates (PZT), low temperature co-fired ceramics and silica glasses are used in several of Sandia's mission critical components. Brittle fracture, either during machining and processing or after many years in service, remains a serious reliability and cost issue. Despite its technological importance, brittle fracture remains poorly understand, especially the onset and propagation of sub-critical cracks. However, some insights into the onset of fracture… more
Date: April 1, 2007
Creator: Hoyt, Jeffrey John
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

FWP executive summaries: basic energy sciences materials sciences and engineering program (SNL/NM).

Description: This report presents an Executive Summary of the various elements of the Materials Sciences and Engineering Program which is funded by the Division of Materials Sciences and Engineering, Office of Basic Energy Sciences, U.S. Department of Energy at Sandia National Laboratories, New Mexico. A general programmatic overview is also presented.
Date: July 1, 2006
Creator: Samara, George A. & Simmons, Jerry A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Development of 1800F-400F Fibrous-Type Insulation for Radioisotope Power Systems. Phase I, Final Report. Volume I.

Description: Thee MIN-K formulations were developed and evaluated for lead-telluride and silicon-germanium radioisotope thermoelectric generatory service. formulation has certain optimum characteristics which govern its use, such as intricate service adjacent o lead-telluride elements, bulk load-bearing service to 1400F, or non-load-bearing service to 1800F. All there formulations were designed to have minimum outgassing characteristics
Date: January 1, 1967
Creator: Collins, J. O.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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