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[Ceramics Factory]

Description: Photograph of a Chinese ceramics factory. In the foreground, vases and dishes are laid out on wooden racks. Terracotta vessels are piled up in woven baskets in the center. Two people stand in front of a kiln in back. More racks are visible in the background.
Date: unknown
Creator: Gough, Ray
Partner: UNT College of Visual Arts + Design

[Ceramics Workshop]

Description: Photograph of a ceramics workshop in China. A row of pitchers are visible on a table in the foreground. A woman sits behind the table painting one of the pitchers. Other tables and workers are visible behind her.
Date: unknown
Creator: Gough, Ray
Partner: UNT College of Visual Arts + Design

Fuels and Materials Development Program Quarterly Progress Report, September 30, 1968

Description: From Foreword: "Report containing information about ongoing research and development taking place in the Oak Ridge National Laboratory's Fuels and Materials Development Program. This includes a series of test reports covering such subjects as reactor fuels, the development of nitride fuels, and the effects of radiation on structural materials."
Date: February 1969
Creator: Oak Ridge National Laboratory. Metals and Ceramics Division.
Partner: UNT Libraries Government Documents Department

Oak Ridge Metals and Ceramics Division Annual Progress Report: 1993

Description: Report documenting research and developments made by the Metals and Ceramic Division of the Oak Ridge National Laboratory. This report provides an overview of activities and accomplishsments of the division from October 1992 through December 1993; the division is organized to provide technical support, mainly in the area of high-temperature materials, for technologies being developed by DOE. Activities span the range from basic research to industrial interactions (cooperative research and technology transfer). Sections 1-5 describe the different functional groups (engineering materials, high-temperature materials, materials science, ceramics, nuclear fuel materials). Sect. 6 provides an alternative view of the division in terms of the major programs, most of which cross group lines. Sect. 7 summarizes external interactions including cooperative R and D programs and technology transfer functions. Finally, Sect. 8 briefly describes the division`s involvement in educational activities. Several organizational changes were effected during this period.
Date: July 1994
Creator: Oak Ridge National Laboratory. Metals and Ceramics Division.
Partner: UNT Libraries Government Documents Department

Oak Ridge Metals and Ceramics Division Annual Progress Report: 1963

Description: Report documenting research and developments made by the Metals and Ceramic Division of the Oak Ridge National Laboratory. Progress is reported on fundamental research in: crystal physics, reactions at metal surfaces, spectroscopy of ionic media, structure of metals, theory of alloying, physical properties, sintering, deformation of crystalline solids, x ray diffraction, metallurgy of superconducting materials, and electron microscope studies. Long-randge applied research studies were conducted for: zirconium metallurgy, materials compatibility, solid reactions, fuel element development, mechanical properties, non-destructive testing, and high-temperature materials. Reactor development support work was carried out for: gas-cooled reactor program, molten-salt reactor, high-flux isotope reactor, space-power program, thorium-utilization program, advanced-test reactor, Army Package Power Reactor, Enrico Fermi fast-breeder reactor, and water desalination program. Other program activities, for which research was conducted, included: thermonuclear project, transuraniunn program, and post-irradiation examination laboratory. Separate abstracts were prepared for 30 sections of the report. (B.O.G.)
Date: November 11, 1963
Creator: Oak Ridge National Laboratory. Metals and Ceramics Division.
Partner: UNT Libraries Government Documents Department

Degradation of structural ceramics by erosion

Description: Materials wastage by solid-particle erosion can be severe and can limit lifetimes. This paper will review the theoretical description of solid-particle erosion in brittle materials, which is well-developed for monolithic ceramics. The models can usually account for effects from the principal projectile properties of size, impact velocity, and impact angle. Materials parameters such as fracture toughness and hardness can be included. Steady-state erosion measurements on a wide variety of ceramics, ranging from Si single crystals to SiC-whisker-reinforced Al{sub 2}O{sub 3}, are reviewed and compared with the models. It is believed that R-curve behavior and/or particle fragmentation is responsible for discrepancies between theory and experimental results for composite ceramics. In addition, the theories make no attempt to describe threshold or incubation effects.
Date: December 1, 1994
Creator: Routbort, J.L.
Partner: UNT Libraries Government Documents Department

Toughening behavior in ceramics and cermets

Description: The development of high strength ({ge} 1 GPa), high toughness ({ge} 10 MPa {radical}m) ceramic systems is being examined using two approaches. In silicon nitride, toughening is achieved by the introduction of large prismatic shaped grains dispersed in a fine grain matrix. For the system examined herein, both the microstructure and the composition must be controlled. A distinctly bimodal distribution of grain diameters combined with controlled yttria to alumina ratio in additives to promote interfacial debonding is required. Using a cermet approach, ductile Ni{sub 3}Al-bonded TiC exhibited toughening due to plastic deformation within the Ni{sub 3}Al binder phase assisted by interfacial debonding and cleavage of TiC grains. The TiC-Ni{sub 3}Al cermets have toughness values equal to those of the WC-Co cermets. Furthermore, the TiC-Ni{sub 3}Al cermets exhibit high strengths that are retained in air to temperatures of {approximately} 1,000 C.
Date: October 1, 1998
Creator: Becher, P.F.; Sun, E.Y.; Hsueh, C.H.; Plucknett, K.P.; Kim, H.D.; Hirao, K. et al.
Partner: UNT Libraries Government Documents Department

Rolling Contact Fatigue of Ceramics

Description: High hardness, low coefficient of thermal expansion and high temperature capability are properties also suited to rolling element materials. Silicon nitride (Si{sub 3}N{sub 4}) has been found to have a good combination of properties suitable for these applications. However, much is still not known about rolling contact fatigue (RCF) behavior, which is fundamental information to assess the lifetime of the material. Additionally, there are several test techniques that are employed internationally whose measured RCF performances are often irreconcilable. Due to the lack of such information, some concern for the reliability of ceramic bearings still remains. This report surveys a variety of topics pertaining to RCF. Surface defects (cracks) in Si{sub 3}N{sub 4} and their propagation during RCF are discussed. Five methods to measure RCF are then briefly overviewed. Spalling, delamination, and rolling contact wear are discussed. Lastly, methods to destructively (e.g., C-sphere flexure strength testing) and non-destructively identify potential RCF-limiting flaws in Si{sub 3}N{sub 4} balls are described.
Date: September 1, 2006
Creator: Wereszczak, Andrew A; Wang, W.; Wang, Y.; Hadfield, M.; Kanematsu, W.; Kirkland, Timothy Philip et al.
Partner: UNT Libraries Government Documents Department

Shock compression profiles in ceramics

Description: An investigation of the shock compression properties of high-strength ceramics has been performed using controlled planar impact techniques. In a typical experimental configuration, a ceramic target disc is held stationary, and it is struck by plates of either a similar ceramic or by plates of a well-characterized metal. All tests were performed using either a single-stage propellant gun or a two-stage light-gas gun. Particle velocity histories were measured with laser velocity interferometry (VISAR) at the interface between the back of the target ceramic and a calibrated VISAR window material. Peak impact stresses achieved in these experiments range from about 3 to 70 GPa. Ceramics tested under shock impact loading include: Al{sub 2}O{sub 3}, AlN, B{sub 4}C, SiC, Si{sub 3}N{sub 4}, TiB{sub 2}, WC and ZrO{sub 2}. This report compiles the VISAR wave profiles and experimental impact parameters within a database-useful for response model development, computational model validation studies, and independent assessment of the physics of dynamic deformation on high-strength, brittle solids.
Date: March 1, 1996
Creator: Grady, D.E. & Moody, R.L.
Partner: UNT Libraries Government Documents Department

Ceramics for ATS industrial turbines

Description: US DOE and most US manufacturers of stationary gas turbines are participating in a major national effort to develop advanced turbine systems (ATS). The ATS program will achieve ultrahigh efficiencies, environmental superiority, and cost competitiveness compared with current combustion turbine systems. A major factor in the improved efficiencies of simple cycle ATS gas turbines will be higher operating efficiencies than curren engines. These temperatures strain the limits of metallic alloy and flow-path cooling technologies. Ceramics materials offer a potential alterative to cooled turbine alloys for ATS turbines due to higher melting points than metallics. This paper evaluates ceramics technology and plant economic issues for ATS industrial turbine systems. A program with the objective of demonstrating first-stage ceramic vanes in a commerical industrial turbine is also described.
Date: May 1996
Creator: Wenglarz, R.; Ali, S. & Layne, A.
Partner: UNT Libraries Government Documents Department

Creep in electronic ceramics

Description: High-temperature creep measurements combined with microstructural investigations can be used to elucidate deformation mechanisms that can be related to the diffusion kinetics and defect chemistry of the minority species. This paper will review the theoretical basis for this correlation and illustrate it with examples from some important electronic ceramics having a perovskite structure. Recent results on BaTiO{sub 3}, (La{sub 1{minus}x}Sr){sub 1{minus}y}MnO{sub 3+{delta}}, YBa{sub 2}Cu{sub 3}O{sub x}, Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub x}, (Bi,Pb){sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub x} and Sr(Fe,Co){sub 1.5}O{sub x} will be presented.
Date: April 27, 2000
Creator: Routbort, J. L.; Goretta, K. C. & Arellano-Lopez, A. R.
Partner: UNT Libraries Government Documents Department

The History of Metals and Ceramics Division

Description: The division was formed in 1946 at the suggestion of Dr. Eugene P. Wigner to attack the problem of the distortion of graphite in the early reactors due to exposure to reactor neutrons, and the consequent radiation damage. It was called the Metallurgy Division and assembled the metallurgical and solid state physics activities of the time which were not directly related to nuclear weapons production. William A. Johnson, a Westinghouse employee, was named Division Director in 1946. In 1949 he was replaced by John H Frye Jr. when the Division consisted of 45 people. He was director during most of what is called the Reactor Project Years until 1973 and his retirement. During this period the Division evolved into three organizational areas: basic research, applied research in nuclear reactor materials, and reactor programs directly related to a specific reactor(s) being designed or built. The Division (Metals and Ceramics) consisted of 204 staff members in 1973 when James R. Weir, Jr., became Director. This was the period of the oil embargo, the formation of the Energy Research and Development Administration (ERDA) by combining the Atomic Energy Commission (AEC) with the Office of Coal Research, and subsequent formation of the Department of Energy (DOE). The diversification process continued when James O. Stiegler became Director in 1984, partially as a result of the pressure of legislation encouraging the national laboratories to work with U.S. industries on their problems. During that time the Division staff grew from 265 to 330. Douglas F. Craig became Director in 1992.
Date: January 1, 1999
Creator: Craig, D.F.
Partner: UNT Libraries Government Documents Department

Rolling Contact Fatigue of Ceramics

Description: No Description Available.
Date: August 25, 2006
Creator: Wereszczak, A.A.; Wang, W. (Bournemouth Univ. UK); Wang, Y. (Bournemouth Univ.UK); Hadfield, M. (Bournemouth Univ.UK); Kanematsu, W. (Natl. Inst. of Advan. Industr. Sci. and Technol. Japan); Kirkland, T.P. et al.
Partner: UNT Libraries Government Documents Department

Transformation Toughening in Ceramics

Description: The origin of transformation toughening in ceramics is examined using two separate approaches: one based on the stress field ahead of the crack and the other on the changes in thermodynamic potential during a crack increment. Both approaches yield essentially similar predictions of trends in toughness with particle size, temperature, composition, etc. The stress intensity analysis provides fully quantitative predictions of the toughness. These indicate that the shielding of the crack by the transformation zone only develops in the presence of a transformed wake, leading to R-curve behavior.
Date: December 1, 1980
Creator: Evans, A. G.; Marshall, D. B. & Burlingame, N. H.
Partner: UNT Libraries Government Documents Department

Superplastic ceramics and intermetallics and their potential applications

Description: Recent advances in the basic understanding of superplasticity and superplastic forming of ceramics and intermetallics are reviewed. Fine-grained superplastic ceramics, including yttria-stabilized tetragonal zirconia polycrystal, Y- or MgO-doped Al{sub 2}O{sub 3} Hydroxyapatite, {beta}-spodumene glass ceramics, Al{sub 2}0{sub 3}-YTZP two-phase composites, SiC-Si{sub 3}N{sub 4} and Fe-Fe{sub 3}C composites, are discussed. Superplasticity in the nickel-base (e.g., Ni{sub 3}Al and Ni{sub 3}Si) and titanium-base intermetallics (TiAl and T1{sub 3}Al), is described. Deformation mechanisms as well as microstructural requirements and effects such as grain size, grain growth, and grain-boundary phases, on the superplastic deformation behavior am addressed. Factors that control the superplastic tensile elongation of ceramics are discussed. Superplastic forming, and particularly biaxial gas-pressure forming, of several ceramics and intermetallics are presented with comments on the likelihood of commercial application.
Date: November 1, 1994
Creator: Wadsworth, J. & Nieh, T.G.
Partner: UNT Libraries Government Documents Department

Environmental microcracking of [NZP] type ceramics

Description: NZP ceramics (sodium zirconium phosphate and its crystal structure analogs) have very low thermal expansion through a large temperature range. Some compositions, with a high degree of thermal expansion anisotropy, are prone to microcracking upon cooling to room temperature. The onset of microcracking is a function of sintering temperature and hence grain size. Subsequent thermal cycling affects the thermal expansion behavior of highly anisotropic compositions due to microcrack healing. Recently it has been determined that this microcracking behavior can be delayed or enhanced by controlling the atmosphere in which the ceramic is heated and cooled. The effects of various atmospheres on the thermal expansion of isotropic and anisotropic [NZP] compositions are presented.
Date: December 31, 1994
Creator: Jackson, T.B. & Porter, W.D.
Partner: UNT Libraries Government Documents Department

Joining NZP ceramics. Final report

Description: Objective was to assess techniques for joining NZP ceramics, a new family of ceramic materials that have low coefficient of thermal expansion, low thermal conductivity, and excellent thermal-shock resistance. Initially, the authors evaluated laser-beam welding over volatile fluxing agents (ferric oxide, copper oxide, boric acid, and boron nitride). They also examined other laser, arc-welding, brazing, and cold joining techniques. The NZP materials were capable of sustaining the thermal stresses associated with these joining processes without substantial cracking. Of the volatile fluxes, only the copper oxide promoted weld fusion. Efforts to accomplish fusion by laser-beam welding over copper, titanium, stainless steel, yttrium barium copper oxide, fused silica glass, and mullite/alumina were unsuccessful. Gas-tungsten arc welding accompanied by porosity, irregularities, and cracking was achieved on copper sheet sandwiched between NZP tiles. Attempts at conventional oxy-acetylene welding and torch brazing were unproductive. Silica-based oxide mixtures and copper oxide-based materials show potential for development into filler materials for furnace brazing, and phosphate-based cements show promise as a means of cold joining.
Date: September 26, 1995
Creator: Nicklas, K.D.; Richey, M.W.; Holcombe, C.E. Jr. & Santella, M.L.
Partner: UNT Libraries Government Documents Department