The vanadium-gallium system in the region of V3Ga
Vanadium-gallium system in region of V-3Ga studied by X-ray diffraction and metallography techniques
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Vanadium-gallium system in region of V-3Ga studied by X-ray diffraction and metallography techniques
Solubility range of 75 atomic percent vanadium- gallium system to determine phases in equilibrium and ascertain presence or absence of superconductivity
Chromium-vanadium alloys for brazing tungsten to molybdenum in engine application
Bonding, structure, and mechanical behavior of vanadium carbide single crystals
Magnetization in superconducting vanadium and niobium not parallel to applied field, using torque measurements
Vanadium concentrations in meteoritic irons and sulfide modules from iron meteorites determined by neutron activation
Radiation damage of vanadium carbide lattice by electron microscope beam bombardment
Solubility of vanadium in liquid potassium
Electron microprobe analysis of vanadium in presence of titanium by compositional measurement of chromite in chondritic meteorites
Low temperature specific heat measurements on vanadium carbide crystals
Terrestrial and chondrites vanadium isotopic ratios indicating irradiation histories difference
Magnetic susceptibility of vanadium carbide from 77 to 300 K measured by magnetometer
Single crystal vanadium carbide magnetic susceptibility decrease with increasing carbon content attributed to orbital paramagnetism
Apollo 12 lunar samples 12002,128, 12021,49, 12038,43 and 12070,52 vanadium isotopic composition
Irradiation effects on three materials from the NASA Plum Brook Reactor Surveillance Program were determined. An increase of 105 K in the nil-ductility temperature for A-201 steel was observed at a fluence of approximately 3.1 x 10 to the 18th power neutrons/sq cm (neutron energy E sub n greater than 1.0 MeV). Only minor changes in the mechanical properties of 17-7 PH stainless steel were observed up to a fluence of 2 x 10 to the 21st power neutrons/sq cm (E sub n greater than 1.0 MeV). The titanium-6-percent-aluminum-4-percent-vanadium alloy maintained its notch toughness up to a fluence of 1 x 10 to the 21st power neutrons/sq cm (E sub n greater than 1.0 MeV).
The effects are sought of an energetic charged particle irradiation of solar system material which is postulated as having taken place early in its history. A similar irradiation took place much more recently in the history of lunar samples and meteorites and this process is studied by means of a variety of monitors including highly sensitive noble gas nuclides, radionuclides, and tracks. Such monitors cannot be used to study the postulated early irradiation since it could have taken place under conditions such that these monitors were not retained or were subsequently lost. Accordingly, it is necessary that a nongaseous element be used to search for the effects of this irradiation, and one of the most sensitive of these is the vanadium isotopic composition. A comparative study is made of the 50 sub V/51 sub V ratios in 15 meteoritic, 5 terrestrial, and 11 lunar samples.
A titanium - 6-percent-aluminum - 4-percent-vanadium alloy (Ti-6Al-4V) was subjected to fretting-wear exposures against uncoated Ti-6Al-4V as a baseline and against various coatings and surface treatments applied to Ti-6Al-4V. The coatings evaluated included plasma-sprayed tungsten carbide with 12 percent cobalt, aluminum oxide with 13 percent titanium oxide, chromium oxide, and aluminum bronze with 10 percent aromatic polyester; polymer-bonded polyimide, polyimide with graphite fluoride, polyimide with molybdenum disulfide (MoS2), and methyl phenyl silicone bonded MoS2, preoxidation surface treatment, a nitride surface treatment, and a sputtered MoS2 coating. Results of wear measurements on both the coated and uncoated surfaces after 300,000 fretting cycles indicated that the polyimide coating was the most wear resistant and caused the least wear to the uncoated mating surface.
Experiments were conducted to determine the friction and wear characteristics of aluminum bronzes and copper-tin, titanium-tin, and copper-silver alloys sliding against a titanium-6% aluminum-4% vanadium alloy (Ti-6Al-4V). Hemispherically tipped riders of aluminum bronze and the titanium and copper alloys were run against Ti-6Al-4V disks in air at 430 C. The sliding velocity was 13 cm/sec, and the load was 250 g. Results revealed that high tin content titanium and copper alloys underwent significantly less wear and galling than commonly used aluminum bronzes. Also friction force was less erratic than with the aluminum bronzes.