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in subjects: "Young Modulus"

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An Ultrasonic Measurement System for the Precise Determination of the Elastic Moduli of Single Crystals

The measurement of the ultrasonic wave velocities in a sufficient number of known directions in a single crystal makes possible the direct computation of the elastic moduli of the crystal. For specimens having linear dimensions on the order of 2 to 3 mm, phase comparison techniques were found useful. The equipment described is based on the technique developed by McSkimin. The measurement system is actually a type of acoustic interferometer adapted to small solid specimens, and it requires speci… more

Date: May 1, 1961

Creator: Renken, C. J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Property changes in near-isotropic graphites irradiated at 300$sup 0$ to 600$sup 0$C: a literature survey

No Description Available.

Date: June 13, 1975

Creator: Price, R.J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Estimates of in situ deformability with an NX borehole jack, Spent Fuel Test - Climax, Nevada test site

A series of borehole modulus measurements was obtained at the Spent Fuel Test - Climax (SFT-C) facility following removal of heat sources and a subsequent 1-year cooling period. A total of 212 measurements were obtained using a standard hardrock NX borehole (Goodman) jack. The results of 64 measurements made at the site before heating were reanalyzed for comparison with the post-heat data. Modulus values were calculated from the straight-line portion of the pressure vs displacement curves. Alth… more

Date: December 1, 1985

Creator: Patrick, W. C.; Yow, J. L., Jr. & Axelrod, M. C.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Development of dense ceramic membranes for methane conversion

The most significant cost associated with partial oxidation of methane to syngas is that of the oxygen plant. In this paper, the authors offer a technology, based on dense ceramic membranes, that uses air as the oxidant for methane conversion reactions, thus eliminating the need for the oxygen plant. Certain ceramic materials exhibit both electronic and ionic conductivities (of particular interest is oxygen-ion conductivity). These materials transport not only oxygen ions (functioning as select… more

Date: June 1, 1995

Creator: Balachandran, U.; Dusek, J. T.; Maiya, P. S.; Ma, B.; Mieville, R. L.; Kleefisch, M. S. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Hierarchical Cellular Materials

In this paper a method for estimating the contributions of both the composite and the cellular microstructures to the overall material properties and the mechanical efficiency of natural cellular solids will be described. The method will be demonstrated by focusing on the Young's modulus; similar techniques can be used for other material properties. The results suggest efficient microstructures for engineered cellular materials.

Date: January 1, 1991

Creator: Gibson, L. J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Hierarchical Cellular Materials

In this paper a method for estimating the contributions of both the composite and the cellular microstructures to the overall material properties and the mechanical efficiency of natural cellular solids will be described. The method will be demonstrated by focusing on the Young`s modulus; similar techniques can be used for other material properties. The results suggest efficient microstructures for engineered cellular materials.

Date: December 31, 1991

Creator: Gibson, L. J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Laboratory Evaluation of Damage Criteria and Creep Parameters of Tioga Dolomite and Rock Salt from Cavern Well No. 1

A suite of laboratory triaxial compression and triaxial steady-state creep tests provide quasi-static elastic constants and damage criteria for bedded rock salt and dolomite extracted from Cavern Well No.1 of the Tioga field in northern Pennsylvania. The elastic constants, quasi-static damage criteria, and creep parameters of host rocks provides information for evaluating a proposed cavern field for gas storage near Tioga, Pennsylvania. The Young's modulus of the dolomite was determined to be 6… more

Date: April 1, 2002

Creator: Lee, Moo Y. & Ehgartner, Brian L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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A method for measuring non-linear elastic properties of thermal barrier coatings

Accurate characterization of the elastic properties of thermal barrier coatings (TBC`s) is important for failure prediction. Thermally sprayed coatings often exhibit anisotropic and nonlinear elastic properties due to the coating microstructure that results from the thermal spray process. A method was developed for determining the elastic behavior of TBC`s on substrates by measuring the in-plane modulus as a function of residual coating stress. The in-plane modulus was determined by resonant fr… more

Date: June 1, 1995

Creator: Johnson, C. A.; Ruud, J. A.; Kaya, A. C. & deLorenzi, H. G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Formation strength parameters from acoustic and density logs in emplacement holes

A new acoustic tool for dry emplacement holes has been built and tested in several emplacement holes. This tool uses a large hammer source and 3 piezo-electric transducers that are independently pressed against the borehole wall. The detectors are 6, 9 and 12 ft from the hammer source. A pure gel is injected between these detectors and the borehole wall to eliminate any air space. The compressional wave travel time and the shear wave travel time are recorded at each detector. The compressional … more

Date: January 1, 1991

Creator: Mathews, M. A.; Fenster, R. A. & Plannerer, H. N.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Mechanical properties of porous PNZT polycrystalline ceramics

Niobium-doped lead zirconate-titanate (PNZT) was used to investigate the effect of porosity on the mechanical properties of a polycrystalline ceramic. Spherical pores (110 to 150 ..mu..m diameter) were introduced by using organic materials in the initial specimen fabrication. The matrix grain size (2 to 5 ..mu..m) was kept constant. Small pores (2 to 3 ..mu..m diameter) of the order of the grain size were formed by varying the sintering conditions. The effect of porosity on strength was predict… more

Date: August 1, 1977

Creator: Biswas, Dipak R. & Fulrath, Richard M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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In-situ physical properties measurements using crosswell acoustic data

Crosswell acoustic surveys enable the in-situ measurements of elastic moduli, Poisson's ratio, porosity, and apparent seismic Q of gas-bearing low-permeability formations represented at the Department of Energy Multi-Well Experiment (MWX) site near Rifle, Colorado. These measurements, except for Q, are compared with laboratory measurements on core taken from the same depths at which the crosswell measurements are made. Seismic Q determined in situ is compared to average values for sandstone. Po… more

Date: January 1, 1985

Creator: Johnson, Paul A. & Albright, James N.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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The effect of frequency on Young`s modulus and seismic wave attenuation

Laboratory experiments were performed to measure the effect of frequency, water-saturation, and strain amplitude on Young`s modulus and seismic wave attenuation on rock cores recovered on or near the site of a potential nuclear waste repository at Yucca Mountain, Nevada. The purpose of this investigation is to perform the measurements using four techniques: cyclic loading, waveform inversion, resonant bar, and ultrasonic velocity. The measurements ranged in frequency between 10{sup {minus}2} an… more

Date: July 1, 1994

Creator: Price, R. H.; Martin, R. J., III & Haupt, R. W.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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The influence of strain rate and sample inhomogeneity on the moduli and strength of welded tuff

A series of constant strain rate, unconfined compression experiments was performed on saturated welded tuff specimens collected from Busted Butte near Yucca Mountain, Nevada. Twenty specimens were loaded to failure at strain rates ranging from 10{sup {minus}9}s{sup {minus}1} to 10{sup {minus}3}s{sup {minus}1}, under ambient pressure and temperature conditions. The strength of the specimens showed a continuous decrease with decreasing strain rate between 10{sup {minus}9} s{sup {minus}1} and 10{s… more

Date: December 31, 1992

Creator: Martin, R. J., III; Boyd, P. J.; Noel, J. S. & Price, R. H.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Effects of fast-neutron damage from 0 to 42 x 10$sup 21$ neutrons/CM$sup 2$ on the physical properties of near-isotropic grades of graphite

No Description Available.

Date: January 1, 1975

Creator: Cook, W. H.; Kennedy, C. R. & Eatherly, W. P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Effects of elevated temperature and pore pressure on the mechanical behavior of Bullfrog tuff

Samples of the Bullfrog Member of the Crater Flat Tuff from the depth interval 758.9 to 759.2 m in hole USW-G1 on the Nevada Test Site were tested in triaxial compression. Test conditions were: (1) effective confining pressure to 20 MPa; (2) temperature of 200{sup 0}C; (3) both dry and with pore water pressures from 3.4 to 5 MPa; and (4) a strain-rate of 10{sup -4}/s. The results suggest that the presence of water causes the strength to decrease. In addition, the brittle-ductile transition pres… more

Date: February 1, 1982

Creator: Olsson, W. A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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An explanation for the shape of nanoindentation unloading curves based on finite element simulation

Current methods for measuring hardness and modulus from nanoindentation load-displacement data are based on Sneddon`s equations for the indentation of an elastic half-space by an axially symmetric rigid punch. Recent experiments have shown that nanoindentation unloading data are distinctly curved in a manner which is not consistent with either the flat punch or the conical indenter geometries frequently used in modeling, but are more closely approximated by a parabola of revolution. Finite elem… more

Date: April 1, 1995

Creator: Bolshakov, A.; Pharr, G. M. & Oliver, W. C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Evaluation of tuff as a waste isolation medium

Tuff is of interest for use as an isolation medium for high heat producing wastes because it provides highly sorptive minerals and suitable thermomechanical properties. Also, tuff is widespread in areas that offer long and deep groundwater flow paths. The occurrence and geologic/hydrologic setting of tuff are discussed. The properties of the rock are discussed and compared with other isolation media. The favorable and unfavorable aspects are presented. Also, unresolved issues are discussed alon… more

Date: December 31, 1979

Creator: Tyler, L. D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Monte Carlo calculations of the anisotropic engineering moduli for crystalline RDX (0 GPa {le} p {le} 4 GPa)

Isothermal-iosbaric Monte Carlo calculations are used in conjunction with an expression that relates the elastic stiffness tensor to the mean-square fluctuations of the strain tensor to obtain first principles predictions of the Young`s moduli, shear moduli, and Poisson`s ratios for room-temperature crystalline RDX. The results are based on numerical data obtained during previously reported calculations of the hydrostatic compression of RDX over the pressure domain 0 GPa {le} p {le} 4 GPa. Alth… more

Date: December 1998

Creator: Bennett, C. M. & Sewell, T. D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Preliminary Strength Measurements of High Temperature Ash Filter Deposits

The objective of this study is to develop and evaluate preliminary strength measurement techniques for high temperature candle filter ash deposits. The efficient performance of a high temperature gas filtering system is essential for many of the new thermal cycles being proposed for power plants of the future. These new cycles hold the promise of higher thermal efficiency and lower emissions of pollutants. Many of these cycles involve the combustion or gasification of coal to produce high tempe… more

Date: December 31, 1996

Creator: Kang, B.S.; Johnson, E.K.; Mallela, R. & Barberio, J.F.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Evaluating mechanical properties of thin layers using nanoindentation and finite-element modeling: Implanted metals and deposited layers

We present a methodology based on finite-element modeling of nanoindentation data to extract reliable and accurate mechanical properties from thin, hard films and surface-modified layers on softer substrates. The method deduces the yield stress, Young`s modulus, and hardness from indentations as deep as 50% of the layer thickness.

Date: December 31, 1996

Creator: Knapp, J.A.; Follstaedt, D.M. & Barbour, J.C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Finite-element modeling of nanoindentation for determining the mechanical properties of implanted layers and thin films

The mechanical properties of implanted layers and thin films on dissimilar substrates are difficult to accurately determine. Nanoindentation of the layer provides information, but detailed numerical modeling is required in order to separate the properties of the layer from those of the substrate. We describe here the procedures we have developed to accomplish this modeling with the commercially available finite-element code ABAQUS. Using these techniques, we are able to extract from nanoindenta… more

Date: October 1, 1996

Creator: Knapp, J. A.; Follstaedt, D. M.; Barbour, J. C. & Myers, S. M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Elastic constants of a Laves phase compound: C15 NbCr{sub 2}

The single-crystal elastic constants of C15 NbCr{sub 2} have been computed by using a first-principles, self-consistent, full-potential total energy method. From these single-crystal elastic constants the isotropic elastic moduli are calculated using the Voigt and Reuss averages. The calculated values are in fair agreement with the experimental values. The implications of the results are discussed with regards to Poisson`s ratio and the direction dependence of Young`s modulus.

Date: April 1, 1997

Creator: Ormeci, A.; Chu, F.; Wills, J. M.; Chen, S. P.; Albers, R. C.; Thoma, D. J. et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Effect of gamma irradiation on the strength of Climax stock quartz monzonite

A laboratory study was made of the effects of a massive dose of {gamma} irradiation upon the mechanical properties of Climax stock quartz monzonite. Twenty-nine cylinders of rocks were tested using the Brazilian method and 26 strain gauged cylinders were tested to failure in uniaxial compression. One-half the cylinders in each group were subjected to a {gamma} ray dose of 13.2 MGy (1.32 x 10{sup 9} rads), or six times the maximum five-year dose to rock at the Spent Fuel Test-Climax, Nevada Test… more

Date: March 31, 1982

Creator: Durham, W.B.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Mechanical and bulk properties of intact rock collected in the laboratory in support of the Yucca Mountain Site Characterization Project

A comprehensive laboratory investigation is determining the mechanical properties of tuffs for the Yucca Mountain Site Characterization Project (YMP). Most recently, experiments have been performed on tuff samples from a series of drill holes along the planned alignment of the Exploratory Study Facilities (ESF) north ramp. Unconfined compression and indirect tension experiments were performed and the results are being analyzed with the help of bulk property information. The results on samples f… more

Date: November 1994

Creator: Price, R. H.; Martin, R. J., III; Boyd, P. J. & Boinott, G. N.

Item Type: Article

Partner: UNT Libraries Government Documents Department