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Effect of Crystal Orientation on Fatigue-Crack Initiation in Polycrystalline Aluminum Alloys

Description: Report presenting testing demonstrating that fatigue cracks initiate in preexisting slip bands on planes parallel to planes from tests on large-grained specimens of 1100 and 5052 aluminum alloys. The resolved shear stress on the planes in crystal where fatigue cracks had developed were compared to uncracked crystals. Results regarding the location fatigue cracks, number of stress cycles observed, and differences of the crystals observed in the two types of aluminum alloys are provided.
Date: August 1957
Creator: Weinberg, J. G. & Bennett, J. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effect of simulated service conditions on plastics

Description: Report presenting an investigation of the effects of simulated surface conditions, which involved exposure to various combinations of moisture, heat, and ultraviolet light, on the weight, dimensional stability, and flexural properties of reinforced plastics.
Date: July 1947
Creator: Crouse, W. A.; Caudill, D. C. & Reinhart, F. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Calibration of Altimeters Under Pressure Conditions Simulating Dives and Climbs

Description: Report presenting an investigation of a method for the dynamic calibration of aneroid altimeters under conditions of rapidly changing pressures simulating pressure conditions in climbs and dives. Three experimental tests were carried out in order to explore the accuracy and determination of certain variables for optimum functioning.
Date: March 1948
Creator: Johnson, Daniel P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Influence of Plastic Deformation and of Heat Treatment on Poisson's Ratio for 18:8 Chromium-Nickel Steel

Description: Note presenting an effective value of Poisson's ratio for 18:8 Cr-Ni steel computed from values of tensile and torsional moduli of elasticity obtianed in earlier investigations by use of an appropriate formula.
Date: February 1944
Creator: Mebs, R. W. & McAdam, D. J., Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Relief of Residual Stress in Streamline Tie Rods by Heat Treatment

Description: "About two-thirds of the residual stress in cold-worked SAE 1050 steel tie rods was relieved by heating 30 minutes at 600 degrees Fahrenheit. Cold-worked austenitic stainless-steel tie rods could be heated at temperatures up to 1000 degrees Fahrenheit without lowering the important physical properties. The corrosion resistance, in laboratory corrosion test, of straight 18:8 and titanium-treated 18:8 materials appeared to be impaired after heating at temperatures above 800 degrees or 900 degrees… more
Date: November 1941
Creator: Pollard, R. E. & Reinhart, Fred M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effect of Screens in Wide-Angle Diffusers

Description: Note presenting an experimental investigation at low airspeeds of the filling effect observed when a screen or similar resistance is placed across a diffuser. The filling effect is found to be real in that screens can prevent separation or restore separated flow in diffusers even of extreme divergence and to depend principally on screen location and pressure-drop coefficient of the screen.
Date: July 1948
Creator: Schubauer, Galen Brandt & Spangenberg, Wesley G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Pressure Drop in Tubing in Aircraft Instrument Installations

Description: "The theoretical basis of calculation of pressure drop in tubing is reviewed briefly. The effect of pressure drop in connecting tubing upon the operation and indication of aircraft instruments is discussed. Approximate equations are developed, and charts and tables based upon them are presented for use in designing installations of altimeters, air-speed indicators, rate-of-climb indicators, and air-driven gyroscopic instruments" (p. 1).
Date: February 1937
Creator: Wildhack, W. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Fatigue Testing of Wing Beam by the Resonance Method

Description: "Preliminary fatigue tests on two aluminum-alloy wing-beam specimens subjected to reversed axial loading are described. The motion used consists in incorporating one or two reciprocating motors in a resonance system of which the specimen is the spring element. A description is given of the reciprocating motors, and of the method of assembling and adjusting the vibrating system" (p. 1).
Date: August 1938
Creator: Bleakney, William M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Gyroscopic Instruments for Instrument Flying

Description: The gyroscopic instruments commonly used in instrument flying in the United States are the turn indicator, the directional gyro, the gyromagnetic compass, the gyroscopic horizon, and the automatic pilot. These instruments are described. Performance data and the method of testing in the laboratory are given for the turn indicator, the directional gyro, and the gyroscopic horizon. Apparatus for driving the instruments is discussed.
Date: September 1938
Creator: Brombacher, W. G. & Trent, W. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Compressive Tests of a Monocoque Box

Description: "A monocoque box specimen of aluminum alloy was subjected to end compression and the strains in the stringers were measured up to loads at which permanent set became noticeable. The stringer strains at low loads agreed closely with those computed from the assumption of uniform stress distribution. Buckling of the 0.026-inch sheet between stringers and of the 0.075-inch shear web took place at stresses in accord with theoretical values" (p. 1).
Date: August 1939
Creator: Ramberg, Walter; McPherson, Albert E. & Levy, Sam
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effects of Prior Fatigue-Stressing of the Impact Resistance of Chromium-Molybdenum Aircraft Steel

Description: Note presenting a study of the impact behavior of normalized SAE X4130 steel after a variety of repeated stress treatments. Fatigue specimens of several types were used and the effects of surface finish, rest periods, stress amplitude, mean stress, stress concentration, and temperature during repeated stress received consideration.
Date: March 1943
Creator: Kies, J. A. & Holshouser, W. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Tidewater and Weather-Exposure Tests on Metals Used in Aircraft

Description: "Tidewater and weather-exposure tests on various aluminum alloys, magnesium alloys, and stainless steels are now being conducted by the National Bureau of Standards. Exposures were begun in June 1938 and, according to present plans, are to continue over a 3-year period. The methods of exposure and the materials being investigated are described and the more important results obtained up to the conclusion of the first year's exposure are reported" (p. 1).
Date: November 1939
Creator: Mutchler, Willard & Galvin, W. G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Torsion Tests of a Monocoque Box

Description: Report presenting testing of a monocoque box of aluminum alloy, which had torques applied to the ends. The twist, strain in the stringers, plate, and corner posts, and the buckling load were measured. A new analysis was developed for the twisting of a monocoque box reinforced by stringers, corner posts, and bulkheads, and the measured twist agreed within 10 percent of the analytical value.
Date: November 1942
Creator: Levy, Samuel; McPherson, Albert E. & Ramberg, Walter
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Limiting Useful Deflections of Corrugated Metal Diaphragms

Description: Note presenting measurements made on a large number of corrugated diaphragms of similar shapes but of various sizes and various metals. Some of the materials studied include phosphor bronze, beryllium copper, A-Nickel, B-Monel, K-Monel, and Inconel. Results regarding pressure deflection, hysteresis, drift, aftereffect, recovery, and zero shift, and design and selection of diaphragms are provided.
Date: December 1942
Creator: Wildhack, W. A. & Goerke, V. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Large-Deflection Theory of Curved Sheet

Description: Equations are given for the elastic behavior of initially curved sheets in which the deflections are not small in comparison with the thickness, but at the same time small enough to justify the use of simplified formulas for curvature. These equations are solved for the case of a sheet with circular cylindrical shape simply supported along two edges parallel to the axis of the generating cylinder. Numerical results are given for three values of the curvature and for three ratios of buckle lengt… more
Date: May 1943
Creator: Levy, Samuel
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Large-Deflection Theory for End Compression of Long Rectangular Plates Rigidly Clamped Along Two Edges

Description: "The von Karman equations for flat plates are solved beyond the buckling load up to edge strains equal to eight time the buckling strain, for the extreme case of rigid clamping along the edges parallel to the load. Deflections, bending stresses, and membrane stresses are given as a function of end compressive load. The theoretical values of effective width are compared with the values derived for simple support along the edges parallel to the load" (p. 1).
Date: January 1943
Creator: Levy, Samuel & Krupen, Philip
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Bending of Rectangular Plates with Large Deflections

Description: "The solution of von Karman's fundamental equations for large deflections of plates is presented for the case of a simply supported rectangular plate under combined edge compression and lateral loading. Numerical solutions are given for square plates and for rectangular plates with a width-span ratio of 3:1. The effective widths under edge compression are compared with effective widths according to von Karman, Bengston, Marguerre, and Cox and with experimental results by Ramberg, McPherson, and… more
Date: May 1942
Creator: Levy, Samuel
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Heat Delivery in a Compressible Flow and Applications to Hot-Wire Anemometry

Description: Note presenting the development of a generalized potential theory applicable to nonadiabatic and rotational flow in a two-dimensional field. Three partial differential equations are obtained determining the three variables. which are distribution of additional temperature, velocity perturbation, and an auxiliary function characterizing the rotationality of the flow. Application of the results to hot-wire anemometry are discussed.
Date: August 1951
Creator: Tchen, Chan-Mou
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Measurement of altitude in blind flying

Description: In this note, instruments for measuring altitude and rate of change of altitude in blind flying and landing of aircraft and their performance are discussed. Of those indicating the altitude above ground level, the sonic altimeter is the most promising. Its present bulk, intermittent operation, and more or less unsatisfactory means of indication are serious drawbacks to its use. The sensitive type aneroid altimeter is also discussed and errors in flying at a pressure level and in landing are dis… more
Date: August 1934
Creator: Brombacher, W. G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Review of an Investigation of Ceramic Coatings for Metallic Turbine Parts and Other High-Temperature Applications

Description: Note presenting an investigation to develop ceramic coatings that will prolong the life of alloys used in turbines, especially the blades, or permit their use at higher temperatures than would otherwise be predictable. Several steps were taken in order to establish whether or not protective coatings can be developed that will effect such an improvement.
Date: March 1947
Creator: Harrison, W. N.; Moore, D. G. & Richmond, J. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effect of aging on taut rubber diaphragms

Description: As part of an investigation of special compositions of rubber suitable for use as diaphragms for aircraft instruments, six samples were used as taut diaphragms in instruments and allowed to age for five years. Two of the instruments were in operating condition after this period of time and one had remarkably little change in performance. In making the rubber tetraethyl thorium disulfide was employed as a vulcanizing agent.
Date: February 1932
Creator: Strother, D. H. & Henrickson, H. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Arithmetic of Distribution in Multi-Cylinder Engines

Description: Note presenting a consideration of the effect on engine performance of a known inequality of distribution. A measure of perfect distribution is provided and some of the factors that influence the unequal distribution of power among cylinders.
Date: October 1923
Creator: Sparrow, Stanwood W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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