4,794,916 research outputs found
High-temperature mechanical behavior of polycrystalline yttrium-doped barium cerate perovskite
The high-temperature mechanical properties of the mixed ionic-electronic conductor perovskite BaCe0.95Y0.05O3-δ with average grain size of 0.40μm have been studied in compression between 1100 and 1300°C in air at different initial strain rates. The true stress-true strain curves display an initial stress drop, followed by an extended steady-state stage. As the temperature decreases and/or the strain rate increases, there is a transition to a damage-tolerant strain-softening stage and eventually to catastrophic failure. Analysis of mechanical and microstructural data revealed that grain boundary sliding is the primary deformation mechanism. The strength drop has been correlated with the growth of ultrafine grains during deformation, already present at grain boundaries and triple grain junctions in the as-fabricated material.Ministerio de Ciencia e Innovación MAT2009-13979-C03-0
Effective Utilizing Wall Conditioning by ICH Main Plasma Discharges for High Ti Mission Experiment
High-temperature ''hydrostatic'' extrusion
Quasi-fluids permit hydrostatic extrusion of solid materials. The use of sodium chloride, calcium fluoride, or glasses as quasi-fluids reduces handling, corrosion, and sealing problems, these materials successfully extrude steel, molybdenum, ceramics, calcium carbonate, and calcium oxide. This technique also permits fluid-to-fluid extrusion
High-temperature-radiation analyzer
Six-channel radiometer with three ultraviolet detection channels measures temperatures at 2-millisecond intervals. One infrared channel measures total radiation, and two infrared channels measure radiation in discrete spectral intervals at rate of 40 intervals per second. Analyzer consists of optical and electrical system
High temperature circuit breaker
Alternating current circuit breaker is suitable for reliable long-term service at 1000 deg F in the vacuum conditions of outer space. Construction materials are resistant to nuclear radiation and vacuum welding. Service test conditions and results are given
High-temperature oxide thermoelectrics
We have evaluated the power factor of transition metal oxides at high
temperatures using the Heikes formula and the Ioffe-Regel conductivity. The
evaluated power factor is found to be nearly independent of carrier
concentration in a wide range of doping, and well explains the experimental
data for cobalt oxides. This suggests that the same power factor can be
obtained with a thermopower larger than , and also suggests a
reasonably high value of the dimensionless figure of merit . We propose an
oxide thermoelectric power generator by using materials having a thermopower
larger than 300 V/K.Comment: 5 pages, 2 figure
High-Temperature Anyon Superconductivity
The screening of an applied magnetic field in the charged anyon fluid at
finite density and temperature is investigated. For densities typical of
high-temperature superconducting materials we find that the anyon fluid
exhibits a superconducting behavior at any temperature. The total Meissner
screening is characterized by two penetration lengths corresponding to two
short-range eigenmodes of propagation within the anyon fluid.Comment: 10 pages Latex 2
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