Model potential calculations of sodium and potassium oscillator strengths
Na and K transition oscillator strengths, noting core polarization effects on mathematical model
Dalgarno, A.↗
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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Cone penetration resistance test - An approach to evaluating in-place strength and packing characteristics of lunar soils
Cone penetration resistance tests on granular lunar soil simulants for in-place shear strength and packing characteristics under various gravity conditions
Cohron, G. T.↗
Approximate analytic solution for the position and strength of shock waves about cones in supersonic flow
Approximate solution for position and strength of shock waves about cones in steady supersonic flow
Davis, S. S.↗
High strength, medium density molded foam
Toluene diisocyanate-based polyurethane produces molded-to-size foam products. Formulation techniques optimize dimension stability, strength and moldability.
Fender, J. R.↗
Fabrication of carbon film composites for high-strength structures
Physical and mechanical properties of fiber composite materials consisting of carbon films are described. Application of carbon film structural composites for constructing microwave filters or optical instruments is proposed. Applications in aerospace and architectural structures for high strength and low density properties are discussed.
Preiswerk, P. R.↗
High strength high modulus ceramic fiber
Low cost method was developed for producing high strength, high modulus, continuous ceramic oxide fibers. Process transforms inexpensive metallic salts into syrup-like liquids that can be fiberized at room temperatures. Resulting salt fibers are then converted to oxides by calcination at relatively low temperatures.
Fetterolf, R. N.↗
Stress corrosion cracking of several high strength ferrous and nickel alloys
The stress corrosion cracking resistance of several high strength ferrous and nickel base alloys has been determined in a sodium chloride solution. Results indicate that under these test conditions Multiphase MP35N, Unitemp L605, Inconel 718, Carpenter 20Cb and 20Cb-3 are highly resistant to stress corrosion cracking. AISI 410 and 431 stainless steels, 18 Ni maraging steel (250 grade) and AISI 4130 steel are susceptible to stress corrosion cracking under some conditions.
Nelson, E. E.↗
Testing methods and techniques: Strength of materials and components. A compilation
The methods, techniques, and devices used in testing the mechanical properties of various materials are presented. Although metals and metal alloys are featured prominently, some of the items describe tests on a variety of other materials, from concrete to plastics. Many of the tests described are modifications of standard testing procedures, intended either to adapt them to different materials and conditions, or to make them more rapid and accurate. In either case, the approaches presented can result in considerable cost savings and improved quality control. The compilation is presented in two sections. The first deals specifically with material strength testing; the second treats the special category of fracture and fatigue testing.
Source record↗
Protective claddings for high strength chromium alloys
The application of a Cr-Y-Hf-Th alloy as a protective cladding for a high strength chromium alloy was investigated for its effectiveness in inhibiting nitrogen embrittlement of a core alloy. Cladding was accomplished by a combination of hot gas pressure bonding and roll cladding techniques. Based on bend DBTT, the cladding alloy was effective in inhibiting nitrogen embrittlement of the chromium core alloy for up to 720 ks (200hours) in air at 1422 K (2100 F). A significant increase in the bend DBTT occurred with longer time exposures at 1422 K or short time exposures at 1589 K (2400 F).
Collins, J. F.↗
Bearing strength of the lunar soil
A discussion is presented on the bearing strength and bearing load-penetration relations in lunar soil. These were measured in air as a function of bulk density. It was found that the relation between bulk density and the logarithm of the bearing capacity is about linear. Shapes of the load vs penetration curves were observed to be similar to those obtained with particulate material of terrestrial origin.
Jaffe, L. D.↗
Composition dependence of ion diffusion coefficients in gas mixtures at arbitrary field strengths
Expressions for the diffusion coefficient of ions in gas mixtures are obtained from momentum transfer theory, and are given in terms of the diffusion coefficients and drift velocities of the ions in the pure component gases. Blanc's law holds exactly at all field strengths if the mean free time between collisions is independent of velocity (Maxwell model), but otherwise there may be either positive or negative deviations from Blanc's law at high fields. Such deviations are of comparable magnitude for the diffusion coefficients and the mobility, but are not identical. Specific cases of inverse-power potentials are treated in further detail, and some numerical examples are given for rigid-sphere interactions.
Whealton, J. H.↗
The strengths of H2O lines in the 8200 A region and their application to high dispersion spectra of Mars.
The improvement in the quality of spectroscopic plates taken in recent years in the search for water vapor in the atmosphere of Mars has dictated the need for improved laboratory data with which to interpret the spectra. This paper presents the results of measurements of the strengths of 41 lines of the 8200 A (211) water vapor band. The measured values show evidence of vibration-rotation interactions on the line intensities, beyond the principal stretching effect.
Farmer, C. B.↗
Deformation, recrystallization, strength, and fracture of press-forged ceramic crystals.
Sapphire and ruby were very difficult to press-forge because they deformed without cracking only in a limited temperature range before they melted. Spinel crystals were somewhat easier and MgO, CaO, and TiC crystals much easier to forge. The degree of recrystallization that occurred during forging (which was related to the ease and type of slip intersections) varied from essentially zero in Al2O3 to complete (i.e., random polycrystalline bodies were produced) in CaO. Forging of bi- and polycrystalline bodies produced incoherent bodies as a result of grain-boundary sliding. Strengths of the forged crystals were comparable to those of dense polycrystalline bodies of similar grain size. However, forged and recrystallized CaO crystals were ductile at lower temperatures than dense hot-pressed CaO. This behavior is attributed to reduced grain-boundary impurities and porosity. Fracture origins could be located, indicating that fracture in the CaO occurs internally as a result of surface work hardening caused by machining.-
Rice, R. W.↗
Compressive strength of titanium alloy skin-stringer panels selectively reinforced with boron-aluminum composite.
Description of a method of selectively reinforcing conventional titanium airframe structure with unidirectional boron-aluminum composite attached by brazing which has been successfully demonstrated based on compression tests of short skin-stringer panels. Improvements in structural performance exceeded 25% on an equivalent weight basis over the range from room temperature to 800 F, both in terms of initial buckling and maximum strengths. Room-temperature performance was not affected by prior exposure at 600 F for 1000 hours in air, or by 400 cycles between -65 and 600 F. The experimental results were generally predictable on the basis of existing analytical procedures. No evidence of failure was observed in the braze bond between the boron-aluminum composite and the titanium alloy.
Herring, H. W.↗
Radiative lifetimes and absolute oscillator strengths for the SiO A/super 1/Pi to X/super 1/Sigma+ transition.
Measurement of a radiative lifetime of 9.6 (plus or minus 1.0) nsec for the SiO A(super 1)Pi state is reported. RKR Franck-Condon factors have been computed and, with these, absolute oscillator strengths are calculated. A band system at 3022 A has been found that may be due to SiO+, but the band is not resolved at our experimental resolution, and identification remains uncertain. The upper state of the carrier of this spectrum has a radiative lifetime of 8.3 (plus or minus 0.8) nsec.
Smith, W. H.↗
The oscillator strengths of the SO /A 3Pi/-/X 3Sigma-/ band systems.
The oscillator strengths for these SO transition band systems are calculated using RKR Franck-Condon factors and the radiative lifetime previously derived from electron-beam phase-shift measurements by Smith (1971). The SO transition concerned is of considerable astrophysical importance in the search for SO in the interstellar medium by means of space-based telescopes with monochromators since the transition probability is concentrated, as shown, in relatively few transitions from the ground state.
Smith, W. H.↗
Welding high-strength aluminum alloys
Handbook has been published which integrates results of 19 research programs involving welding of high-strength aluminum alloys. Book introduces metallurgy and properties of aluminum alloys by discussing commercial alloys and heat treatments. Several current welding processes are reviewed such as gas tungsten-arc welding and gas metal-arc welding.
Parks, P. G.↗
Development of advanced high strength tantalum base alloys. Part 1: Screening investigation
Five experimental tantalum alloy compositions containing 13-18% W+Re+Hf solid solution solute additions with dispersed phase strengthening achieved by carbon or nitrogen additions were prepared as 1.4 inch diameter ingot processed to 3/8 inch diameter rod and evaluated. Elevated temperature tensile and creep strength increased monotonically with increasing solute content. Room temperature elongation decreased for 20% to less than 2% as the solute content was increased above 16%. Phase identification indicated that the precipitating phase in the carbide containing alloys was Ta2C.
Buckman, R. W., Jr.↗