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Nondestructive Measurement of Residual and Enforced Stresses by Means of X-Ray Diffraction 2: Some Applications to Aircraft Problems

Description: Note presenting tests on the use of x-ray diffraction methods for determining surface stress distributions in notched tensile bars and in the vicinity of a welded joint in aircraft steel tubing. Data on the effects of stress and degree of notching on the principal stresses and stress-concentration factors for flat notched tensile-test specimens were obtained.
Date: November 1945
Creator: Sachs, George; Smith, Charles S.; Lubahn, Jack D.; Davis, Gordon E. & Ebert, Lynn J.
Partner: UNT Libraries Government Documents Department

Measurements of Recovery Factors and Coefficients of Heat Transfer in a Tube for Subsonic Flow of Air

Description: Note presenting measurements of heat flow to air at subsonic velocities and substantially constant Reynolds number, which show that the heat-transfer coefficient is independent of the difference between the temperature of the heated wall and the adiabatic wall temperature. Recovery factors are measured at the pipe wall for adiabatic flow.
Date: June 1945
Creator: McAdams, William H.; Nicolai, Lloyd A. & Keenan, Joseph H.
Partner: UNT Libraries Government Documents Department

Nondestructive Measurement of Residual and Enforced Stresses by Means of X-Ray Diffraction 1: Correlated Abstract of the Literature

Description: Note presenting a study of the stress measurements by means of the x-ray diffraction method, which have found considerable application in solving both commercial and laboratory problems. Two problems related to x-ray diffraction are studied and a literature review is conducted.
Date: September 1945
Creator: Sachs, George; Smith, Charles S.; Lubahn, Jack D.; Davis, Gordon E. & Ebert, Lynn J.
Partner: UNT Libraries Government Documents Department

On Two-Dimensional Flows of Compressible Fluids

Description: "This report is devoted to the study of two-dimensional steady motion of a compressible fluid. It is shown that the complete flow pattern around a closed obstacle cannot be obtained by the method of Chaplygin. In order to overcome this difficulty, a formula for the stream-function of a two-dimensional subsonic flow is derived" (p. 1).
Date: August 1945
Creator: Bergman, Stefan
Partner: UNT Libraries Government Documents Department

Shear Elastic Properties of Some High Strength Nonferrous Metals as Affected by Plastic Deformation and by Heat Treatment

Description: Note presenting a study of the shear elastic properties of monel, nickel, Inconel, and aluminum-model tubing, as influenced by extension of annealed specimens, by cold reduction during manufacture, and by stress-relief annealing of cold-reduced materials. With slight extension of annealed tubing, the shear proof stresses generally decrease, owing to induced internal stress.
Date: January 1945
Creator: Mebs, R. W. & McAdam, D. J., Jr.
Partner: UNT Libraries Government Documents Department

Friction in Pipes at Supersonic and Subsonic Velocities

Description: Note presenting an experimental determination of the apparent friction coefficient for the flow of air through smooth pipes at subsonic and supersonic velocities. In supersonic flow, the results were found to be strongly influenced by the presence of oblique shocks formed at the junction of nozzle and pipe. Results regarding the apparent friction coefficient, subsonic flow, supersonic flow, and comparisons with other investigations are provided.
Date: January 1945
Creator: Keenan, Joseph H. & Neumann, Ernest P.
Partner: UNT Libraries Government Documents Department

Table of Interplanar Spacings for Crystal-Structure Determinations by X-Ray Diffraction With Molybdenum, Copper, Cobalt, Iron, and Chromium Radiations

Description: "For a simple diffraction pattern, the time required to calculate interplanar distances from measurements of the pattern is not excessive. If more than a few lines are present, however, or if several patterns are to be studied, it is very advantageous to have available a table giving interplanar spacings directly in terms of the linear measurements made on the film of the lines appearing on the diffraction pattern. The preparation of the table given here was undertaken when the expansion of research activities involving X-ray diffraction techniques indicated that such a table would greatly decrease the time required to analyze diffraction patterns" (p. 1).
Date: October 1945
Creator: Kittel, J. Howard
Partner: UNT Libraries Government Documents Department

Effect of Aging Aircraft Structures on Magnesium Parts

Description: Note presenting an analysis of a procedure for artificially aging assemblies and subassemblies to improve the strength properties of the wrought aluminum alloys comprising their principal structure. Information is given on the magnesium alloys which may be present. The forms in which magnesium alloys may be encountered are casings, extrusions, forgings, and sheet.
Date: April 1945
Creator: Winston, A. W.
Partner: UNT Libraries Government Documents Department

Fatigue Tests on 1/8-inch Aluminum Alloy Rivets

Description: Note presenting an investigation of the fatigue characteristics of riveted joints in aluminum alloy sheet. The purpose of this report is to summarize all the results of fatigue tests that have been made to date in the Aluminum Research Laboratories of lap joints with 1/8-inch aluminum alloy rivets.
Date: February 1945
Creator: Andrews, H. J. & Holt, M.
Partner: UNT Libraries Government Documents Department

Bonding Strengths of Adhesives at Normal and Low Temperatures

Description: Note presenting a determination of the bonding strengths of two thermosetting adhesives, liquid Cycleweld C-3 and Ardux 1, to several aircraft materials using shear tests made on lap-joint specimens. The specimens were tested at 25 degrees Celsius and at subfreezing temperatures of approximately -40 degrees Celsius. Results regarding the specimens bonded under clamping pressure, specimens bonded after various surface treatments, specimens of metal bonded to plywood, and specimens of aluminum bonded to magnesium are provided.
Date: January 1945
Creator: Axilrod, B. M. & Jirauch, D. H.
Partner: UNT Libraries Government Documents Department

Force and Moment Coefficients for a Thin Airfoil With Flap and Tab in a Form Useful for Stability and Control Calculations

Description: Note presenting the necessary pressure and force coefficients acting on a thin airfoil with a flap and tab in a form suitable for stability calculations in order to design improved control arrangements.
Date: January 1945
Creator: White, Roland J. & Klampe, Dean G.
Partner: UNT Libraries Government Documents Department

The inward bulge type buckling of monocoque cylinders 3: revised theory which considers the shear strain energy

Description: Report presenting the third part of an investigation dealing with the inward bulge type buckling of monocoque cylinders the theory of buckling in pure bending, which is refined through the consideration of the shear strain energy stored in the sheet covering, the assumption of a revised deflected shape of the rings, and the use of summations in place of some of the integrations of the preceding report.
Date: April 1945
Creator: Hoff, N. J. & Klein, Bertram
Partner: UNT Libraries Government Documents Department

Properties of some expanded plastics and other low-density materials

Description: Report presenting an investigation of various mechanical and physical properties of several expanded plastics and other low-density materials of interest for aircraft applications, such as heat insulation or the core of a sandwich material. The materials in the investigation included cellulose acetate plastic, polystyrene, a urea-formaldehyde resin, a zein product, hard rubber, balsa wood, and cellular glass.
Date: September 1945
Creator: Axilrod, Benjamin M. & Koenig, Evelyn
Partner: UNT Libraries Government Documents Department

Performance tests of wire strain gages 2: calibration factors in compression

Description: Report presenting the results of calibrations in axial compression over the strain range 0 to 0.0021 for 15 types of single element multistrand wire strain gages. The majority of gages showed significant differences between the calibration factors for strain increasing and strain decreasing. The majority of the gages were found to have slightly lower factors in compression than in tension.
Date: September 1945
Creator: Campbell, William R.
Partner: UNT Libraries Government Documents Department

Performance tests of wire strain gages 3: calibrations at high tensile strains

Description: Report presenting results of calibration in axial tension over the strain range 0 to 0.03 are presented for 15 types of single element, multistrand wire strain gages. Considerable nonlinearity was observed at strains between 0.0025 and 0.006. Fifty-eight percent of the gages failed by breaking of the strain-sensitive wire at strains less than 0.03.
Date: December 1945
Creator: Campbell, William R.
Partner: UNT Libraries Government Documents Department

Bearing strengths of 75S-T aluminum-alloy sheet and extruded angle

Description: Report presenting an investigation to determine the bearing yield and ultimate strengths of 75S-T alloy in sheet form in both with- and across-grain directions and extruded angle in the longitudinal direction. Ratios of bearing to tensile properties were also determined.
Date: February 1945
Creator: Wescoat, C. & Moore, R. L.
Partner: UNT Libraries Government Documents Department

Bearing strengths of 24S-T aluminum alloy plate

Description: Report presenting a series of tests to determine the bearing yield and ultimate strengths of samples of 1/4- and 2-inch-thick plate of aluminum alloy 24S-T and to establish nominal ratios of bearing-to-tensile properties for the commercial range of plate thicknesses. Results regarding individual bearing testing, ratios of average bearing to tensile properties, and ratios of bearing yield strength to tensile yield strength are provided.
Date: June 1945
Creator: Moore, R. L. & Wescoat, C.
Partner: UNT Libraries Government Documents Department

Analytical study of transmission of load from skin to stiffeners and rings of pressurized cabin structure

Description: From Introduction: "The investigations in this paper were made to obtain more generalized mathematical analyses of monocoque structure subjected to internal pressure. It is also assumed that the principle of superposition can be applied, so that stress analysis of a structure with combined internal pressure and external load can be made without excessive complication."
Date: October 1945
Creator: Pian, Theodore Hsueh-Huang
Partner: UNT Libraries Government Documents Department

Studies of Blade Shank and Pitch Distribution for Constant-Speed Propellers

Description: Note presenting an experimental investigation of the influences of blade shank form and pitch distribution on the aerodynamic characteristics of constant-speed propellers. The results indicated that the replacement of round blade shanks by faired ones produced substantial improvements of efficiency which increased with the advance ratio. Results regarding blade shank form, pitch distribution, and influences of blade loading and number of blades are provided.
Date: January 1945
Creator: Reid, Elliott G.
Partner: UNT Libraries Government Documents Department

Survey of Adhesives and Adhesion

Description: Report presenting an investigation regarding the strengths of bonds between different chemical types of adhesives and adherends. Some of the topics explored include the theoretical aspects of adhesion and properties of adhesively bonded structures.
Date: August 1945
Creator: Rinker, R. C. & Kline, G. M.
Partner: UNT Libraries Government Documents Department

Strength of Wing Beams Under Axial and Transverse Loads

Description: Note presenting wing beams tested under axial compressive loads, transverse loads, and combined axial and transverse loads. Deflections and strains in the elastic range were in general agreement with those computed from the simple beam theory after taking account of the secondary bending moment produced by the axial load as the beam deflected under load.
Date: September 1945
Creator: Ramberg, Walter; McPherson, A. E. & Levy, Samuel
Partner: UNT Libraries Government Documents Department

Graphical and Analytical Methods for the Determination of a Flow of a Compressible Fluid Around an Obstacle

Description: "Chaplygin introduced the hodograph method in the theory of compressible fluid flows and developed a method for constructing stream functions of such flows. This method, which has been extensively used in investigation of compressible fluid flows, is limited in certain respects. The expression for the stream function obtained in this manner can represent only certain types of flow patterns. In general, flow patterns obtained in this way cannot represent the whole flow around an obstacle, but only a part of such a flow, and therefore several expressions are needed in order to obtain the whole flow" (p. 1).
Date: July 1945
Creator: Bergman, Stefan
Partner: UNT Libraries Government Documents Department

The Elastic Constants for Wrought Aluminum Alloys

Description: "There are several constants which have been devised as numerical representations of the behavior of metals under the action of loadings which stress the metal within the range of elastic action. Some of these constants, such as Young's modulus of elasticity in tension and compression, shearing modulus of elasticity, and Poisson's ratio, are regularly used in engineering calculations. Precise tests and experience indicate that these elastic constants are practically unaffected by many of the factors which influence the other mechanical properties of materials and that a few careful determinations under properly controlled conditions are more useful and reliable than many determinations made under less favorable conditions" (p. 1).
Date: January 1945
Creator: Templin, R. L. & Hartmann, E. C.
Partner: UNT Libraries Government Documents Department