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A compilation, containing articles on a number of analytical techniques for quality control engineers and laboratory workers, is presented. Data cover techniques for testing electronic, mechanical, and optical systems, nondestructive testing techniques, and gas analysis techniques.
Structural design considerations for O2 tank shells and suspension systems of ground based storage and mobile tank systems are outlined. Safety factors, chemical compatibility, liquid slosh strength, and cryogenic temperature properties are summarized. Finally, costs, quality control measures, and long life characteristics are examined.
Materials and design considerations are discussed for a low-cost, reliable radio-isotope-fueled thermoelectric generator for use in an undersea application. Plutonium has been selected as fuel, and the generator has to meet design goals of 2 watts after 20 years with a direct output voltage of 6-8 volts. The pressed and sintered form of Bi2Te3 appears to be the most appropriate thermoelectric material. Both fibrous and multilayer foil insulation could be used with proper processing and quality control, but there is less risk with fibrous type insulation. Min-K 1400 is recommended with a nitrogen cover gas. The heat source recommended is a three-layer capsule using T-111 for both the liner and strength member with an outer liner of Hastelloy-C.
Report discusses number of tests used in comparing polymer adhesives with metal bonding processes and includes charts and photographs to illustrate test results. Findings suggest reduced quality control costs when epoxies are used in fabrication of microcircuits.
Set of standards in the form of drawings provides detailed information about materials fastening techniques, surface finishes, critical dimensions, quality control specifications, and installation methods for variety of static and total pressure tube instrumentation.
Failure mechanisms, test techniques, and quality control procedures for difficult-to-detect class of failures have been devised. Test circuit provides electrostatic discharge similar to those encountered in production situation and assists in evaluation of susceptibility of specific circuits and devices
Strength ratios are reported which were derived from slow bend tests on 0.25 inch thick precracked Charpy specimens of steels, aluminum alloys, and a titanium alloy for which valid K sub Ic values were established. The strength ratios were used to develop calibration curves typical of those that could be useful in estimating K sub Ic for the purposes of alloy development of quality control.
Material specification and fabrication process procedures for foam production are presented. The properties of mechanical strength, modulus of elasticity, density and thermal conductivity were measured and related to foam quality. Properties unique to the foam such as a gas layer insulation, density gradient parallel to the fiber direction, and gas flow conductance in both directions were correlated with foam quality. Inspection and quality control tests procedures are outlined and photographs of test equipment and test specimens are shown.
The operational river basin snow mapping program at NESS is described with emphasis on quality control techniques and results for the 1974-1975 snow season.
The non spin platform is a means for achieving the very low acceleration requirements for cost effective space processing experiments on research rocket flights. These platforms have a low initial cost, are re-usable and have extremely low refurbishment cost. In order to attain this goal, commercially available components were used and only the necessary quality control standards were imposed. A detailed system description, the very few design problems encountered, the operational procedures (both pre-flight and post-flight), and the maintenance requirements are described.
APFO furnishes LANDSAT imagery and supporting NASA aircraft imagery to NASA-funded principal investigators who are working within the agriculture discipline. The office holds and reproduces Skylab imagery and a variety of aircraft photography (including infrared) from various government agencies. Available products are listed. Other topics discussed include quality control of photographic materials, analytical aerotriangulation, and photographic processes.
Management is a compilation of references to selected reports, journal articles, and other documents on the subject of management. This publication lists 368 documents originally announced in the 1975 issues of Scientific and Technical Aerospace Reports (STAR) or International Aerospace Abstracts (IAA). It includes references on the management of research and development, contracts, production, logistics, personnel, safety, reliability and quality control. It also includes references on: program, project and systems management; management policy, philosophy, tools, and techniques; decisionmaking processes for managers; technology assessment; management of urban problems; and information for managers on Federal resources, expenditures, financing, and budgeting.
The two dimensional static and dynamic current density distributions within the junction of semiconductor power switching devices and in particular the thyristors were obtained. A method for mapping the thermal profile of the device junctions with fine resolution using an infrared beam and measuring the attenuation through the device as a function of temperature were developed. The results obtained are useful in the design and quality control of high power semiconductor switching devices.
Data from routine ozone monitoring in southeastern Wisconsin and limited monitoring of the Milwaukee area by the Environmental Protection Agency are examined. Hourly averages as high as 30 pphm have been recorded in southeastern Wisconsin, and high readings have been reported in rural regions throughout the state. The observations indicate that photochemical oxidants and their nitrogen oxide and reactive hydrocarbon precursers advect from Chicago and northern Indiana into southeastern Wisconsin. There is evidence that synoptic-scale transport of photochemical oxidants occurs, allowing the pollution of entire anticyclones. These results cast doubt on the validity of the Air Quality Control Regions established by amendment to the Clean Air Act of 1970.
Automatic Monitoring System for time-dependent dielectric breakdown tests ninety-nine metal-oxide semiconductor capacitors simultaneously. Each breakdown generates voltage spike registered on readouts and indicated by LED. Latching circuit prevents recording of possible subsequent breakdowns in same capacitor. In addition to research use, system could also be adapted for quality control.
The parylene coating process developed during this program consists of (1) obtaining a hybrid cover with a hole in it, (2) sealing of the circuit with a hole in the cover, (3) parylene coating through the hole with the external leads protected from parylene by appropriate fixturing, and (4) sealing of the hole by soldering a pretinned kovar tab. Development of the above process required optimization of the parylene coater parameters to obtain a uniform consistent coating which could offer adequate protection to the circuits, fixture design for packages of various types, determination of the size of the deposition hole, and the amount of dimer charge per run, a process to hermetically seal the deposition holes and establishment of quality control techniques or acceptance criteria for the deposited film.
Tests for studying the basic material are considered and quality control investigations involving preimpregnated materials (prepreg) are discussed. Attention is given to the prepreg area weight, the fiber area weight of prepregs, the resin content, volatile components, the effective thickness, resin flow, the resistance to bending strain, tensile strength, and shear strength. A description of tests conducted during the manufacturing process is also presented, taking into account X-ray methods, approaches of neutron radiography, ultrasonic procedures, resonance methods and impedance studies.
A comparison is made between fracture toughness KIc as measured by recommended ASTM procedures and crack arrest toughness KIa as measured on more than 100 bolt-loaded double-cantilever beam (DCB) specimens from 7075, 7050, and 7049 alloy plates. Close agreement was found between the two values, KIa being on the average less than KIc over a specified range. This indicates that a simplified test based on a bolt-loaded DCB specimen could be used for quality control, lot release, and screening purposes. Measurements of crack length and specimen deflection are all that are required. The specimens do not have to be fatigue precracked, nor is a tensile machine needed.