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Vacuum ultraviolet coatings, microcircuitry welding, metal polishing, absolute spectral response system, parabolic reflectors, and soldering to electrodeposited metals
Positive ion beam polishing of optical surfaces
We have developed a new nanochannel fabrication technique using chemical-mechanical polishing (CMP) and thermal oxidation. With this technique, it is possible to control the width, length, and depth of the nanochannels without the need for nanolithography. The use of sacrificial SiO2 layers allows the fabrication of centimeter-long nanochannels. In addition, the fabrication process is CMOS compatible. We have successfully fabricated an array of extremely long and narrow nanochannels (i.e. 10 mm long, 25 nm wide and 100 nm deep) with smooth inner surfaces.
Time variation of total hemispherical emission of polished platinum surfaces at high temperatures
Pool boiling data at atmospheric pressure for mechanically polished and chemically etched 304 stainless steel surfaces in contact with distilled water
Simple, inexpensive device can be attached to most metallographic sample polishing tables. It provides a suitable surface finish for microscopic examination or photography of surface details of the samples.
Physical adsorption of nitrogen gas on polished surface of 347 stainless steel at low pressures
Polished metals exposed to hypervelocity impact by micrometer size projectiles to determine bombardment effect on spectral reflectance
Conforming polisher for aspheric surfaces of revolution with inflatable tube
Hypervelocity projectile material impact on ultimate reflectance of bombarded polished metals from shock tube tests
General principles and details of the actual procedure are presented for the preparator. Some background information is given on why certain lapping, polishing, and gluing procedures are needed. It is directed toward the innovative preparator who wishes to further refine procedures or to use some of his own techniques for some steps in the processing sequence. Specific details on the single procedure found to be most successful for lunar dense rocks, breccias, and particulates are outlined. A complete listing of equipment and supplies is appended.
Development of improved procedures is reported for three classes of lunar materials: dense rocks, breccias, and particulates. High quality ultrathin sections of these materials are obtained. Lists of equipment and supplies, procedures, photomicrographic documentation, and training are provided. Advantages of ultrathin polished sections for conventional and unconventional optical microscopy methods are described. Recommendations are provided for use of ultrathin sections in lunar rock studies, for further refinement of ultrathinning procedures, and for additional training efforts to establish a capability at the Manned Space Center. For Part 2, See N72-50754.
Four optically polished flat samples were tested at wavelengths of 8.34 A, 13.3 A, and 44 A and 0.5 deg, 0.92 deg, 1.5 deg, 2.0 deg and 4.0 deg angle of incidence. The four samples were also tested at 8.34 A and 0.92 deg angle of incidence for three additional angular orientations about an axis normal to the sample surface: 45 deg, 90 deg and 180 deg from the 0 deg position. The tests indicate that the scattering was greater at 44 A than at 13.3 A and 8.34 A. The orientation tests indicated that no great irregularities were present.
Single-crystal sheets pulled from polten silicon floating on refractory melt require no slicing or polishing. Possible materials are chlorides and fluorides of barium, calcium, and strontium. Refractory melt may be able to absorb impurities from silicon and thus obviate postgrowth purification.
The present method for the polishing of near-f/1 aspherics employs a lap whose shape is continuously changed under computer control as it moves over the rigid mirror blank. Required changes of radius, astigmatism, and coma in a circular lap are accomplished by means of edge-bending levers and tensioning members that use screw actuators. Attention is given to the case of an f/1, 8-m diameter paraboloid whose mirror blank has been cast in a centrifugally stressed, rotating furnace to within 1 mm of the desired optical figure. Attention is also given to the mechanical design of the active lap.
Techniques for polishing figured X-ray optics by a lacquer-coating process are described. This acrylic lacquer coating has been applied with an optical quality of an eighth-wave in red light and very effectively covers surface roughness with spatial wavelengths less than about 0.2 mm. Tungsten films have been deposited on the lacquer coatings to provide highly efficient X-ray reflectivity.
Wedged and beveled ends lapped with precision for laser applications. See "Wedge Fibers Suppress Feedback of Laser Beam" (LAR-13074). For obtuse-angled wedge end, both sides of fiber polished similarly. After one side of fiber is lapped, fiber support removed. Holding block with fiber turned over, and fiber support replaced. Second side of fiber then lapped.
Springy abrasive tool used to finish surfaces of narrow cavities made by electrical-discharge machining. Robot arm moves vibrator around perimeters of cavities, polishing walls of cavities as it does so. Tool needed because such cavities inaccessible or at least difficult to reach with most surface-finishing tools.