71,661 research outputs found
Soil crusts on Mars
Three distinct soillike materials sampled by the Viking landers (VL) on Mars are (in order of increasing strength): (1) drift; (2) crusty to cloddy; and (3) blocky. Relative strengths of these materials are manifested by footpad penetrations during landing (VL 1), depths of deep holes, motor currents during sampling, sampler backhoe penetrations, comminutor motor currents, impact pits, trench tailings, and successful acquisitions of the coarse fraction (only blocky material). Cementation by S Cl compounds probably contributes to the relative strengths. This is shown where the weight pct. of SO3 + Cl of each material is plotted against their relative strengths. A similar result is obtained using SO3 alone, but not with Cl which is deficient in VL 2 samples
Martian surface materials
A semiquantitative appreciation for the physical properties of the Mars surface materials and their global variations can be gained from the Viking Lander and remote sensing observations. Analyses of Lander data yields estimates of the mechanical properties of the soil-like surface materials and best guess estimates can be made for the remote sensing signatures of the soil-like materials at the landing sites. Results show that significant thickness of powderlike surface materials with physical properties similar to drift material are present on Mars and probably pervasive in the Tharsis region. It also appears likely that soil-like materials similar to crusty to cloddy material are typical for Mars, and that soil-like material similar to blocky material are common on Mars
Solid state welding of dispersion-strengthened nickel alloys
Two-step solid state welding cycle applied to carefully prepared surfaces of an unrecrystallized alloy prevents loss of parent-metal strength at weld joint of dispersion-strengthened, nickel-chromium alloy
Practical method of diffusion-welding steel plate in air
Method is ideal for critical service requirements where parent metal properties are equaled in notch toughness, stress rupture and other characteristics. Welding technique variations may be used on a variety of materials, such as carbon steels, alloy steels, stainless steels, ceramics, and reactive and refractory materials
Reversible ring counter employing cascaded single SCR stages Patent
Reversible ring counter using cascaded single silicon controlled rectifier stage
Welding blades to rotors
A process is described to form T-joints between dissimilar thickness parts by magnetic force upset welding. This type of resistance welding is used to join compressor and turbine parts which thereby reduces the weight and cost of jet engines
Ring counter may be advanced or retarded by command signal
A power logic circuit, with bidirectional capability, is used to drive small loads in planned sequence. This is designed in the form of a shift register, with a reversible ring counter
Diffusion welding in air
Solid state welding a butt joint by fusion welding the peripheral surfaces to form a seal is described along with, autogenetically cleaning the faying or mating surfaces of the joint by heating the abutting surfaces to 1,200 C and heating to the diffusion welding temperature in air
Apparatus for welding blades to rotors
Using magnetic force upset welding to form T-joints between dissimilar thickness parts. This type of resistance welding is used to join compressor and turbine parts thereby reducing the weight and cost of a jet engine
Waveform simulator Patent
Sign wave generation simulator for variable amplitude, frequency, damping, and phase pulses for oscilloscope displa
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