Two methods of securing a dynamic stress-strain curve are considered: namely, from the measurement of impact stress as a function of maximum plastic strain and impact stress as a function of the impact velocity. The results show that the behavior of annealed 2S Al under condition of impact loading into the plastic strain range can be represented to a good approximation by a single dynamic stress-status relation. This dynamic stress-strain relation lies above the static stress-strain curve. The...

Topics: DTIC Archive, JOHNSON, J. E., WOOD, D. C., CLARK, D. S., CALIFORNIA INST OF TECH PASADENA DYNAMIC...

An analysis was performed to determine the permanent deformation of beams subjected to transverse loading of such a magnitude that the plastic strains produced are large compared to the elastic strains. A satisfactory approximation to the solution of the problems can be obtained by the techniques used in elastic beam theory. The analysis is based on the assumptions (1) that the strain-hardening bending moment-curvature relationship is linear, and (2) that the rate of change of curvature of the...

Topics: DTIC Archive, Conroy, Margaret F., BROWN UNIV PROVIDENCE RI DIV OF APPLIED MATHEMATICS, *CANTILEVER...

The strain distribution in a moderately tapered (10%), transversely stiffened, thin-walled Duralumin box was tested under torsion and/or bending. Direct and shear-strain distributions were measured around representative cross sections with electric resistance strain gages. Comparisons of the test data with theoretical analyses indicated that: (1) maximum direct strains at the root (under shear loads) exceed conventional beam-theory predictions by as much as 20%; and (2) the maximum shear strain...

Topics: DTIC Archive, Falconer, Bruce H., AERONAUTICAL RESEARCH COUNCIL LONDON (UNITED KINGDOM), *TORSION,...

An analysis is presented of the stresses and strains in a fully plastic, initially uniform, rotating annular disk composed of a strain-hardening material. The analysis is based on Tresca's yield condition and the associated flow rule and assumes that elastic strains may be neglected in comparison to the finite plastic strains. The bursting speed of the disk is expressed in terms of a definite integral involving the strain-hardening function of the material. Analytical evaluations are presented...

Topics: DTIC Archive, Weiss, H. J., Prager, W., BROWN UNIV PROVIDENCE RI DIV OF APPLIED MATHEMATICS,...

A perfectly plastic material is assumed which obeys Tresca's yield criterion of constant maximum shearing stress (k) during plastic deformation. The velocity field is also assumed to have axial symmetry. The states of stress involving k are represented by points on the surface of a right prism which has a regular hexagon for its cross section. Plastic flow can occur under states of stress represented by points on the hexagon. The principal axes of the plastic strain rate coincide with the...

Topics: DTIC Archive, Shield, R. T., BROWN UNIV PROVIDENCE RI DIV OF APPLIED MATHEMATICS, *PLASTIC...

Quantitative measurements of the contribution of grain boundary shearing to the creep process were made for high-purity Al in the temperature range 610 deg to 747 deg K under a stress of 250 psi. Grain boundary shearing followed the same functional relationship as the total creep strain, namely, Eg. b. = f(theta), where Eg.b = creep strain due to the grain boundary shearing and theta = te-delta Hg.b/RT(where t = time under stress delta, delta Hg.b. = activation energy for grain boundary...

Topics: DTIC Archive, Fazan, Bernard, Sherby, Oleg D., Dorn, John E., CALIFORNIA UNIV BERKELEY MATERIALS...

An analysis is presented of the scaling parameters which are important in scaling explosive-induced waves in earth materials and the effect of these waves on deep underground structures. Basically, two approaches to scaling are possible. Gravitational effects can be allowed for and material properties scaled, or gravitational effects can be ignored and material properties kept the same in the model as in the prototype. The study indicates that peak strain is dependent upon yield as well as...

Topics: DTIC Archive, Clark, George B, ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS, *ROCK,...

A combination slotted-tube end-burning charge configuration was used to achieve a boost-to-sustain thrust ratio of about 20 in a single chamber motor assembly. The grain was cast in place with a single propellant formulation. Test firings were carried out with both plastisol nitrocellulose composite and HC binder composite propellants containing 1% aluminum. These tests demonstrated rapid and smooth transitions from the high to the low levels of operation with pressure ratios up to 17. No...

Topics: DTIC Archive, Thompson,B L, REDSTONE ARSENAL RESEARCH DIV ROHM AND HAAS CO HUNTSVILLE ALA, *DUAL...

Evaluation of a light metal hydride in CMDB propellants was continued. Distinct improvements in processibility were observed with recent batch production lots. By contrast, the laboratory scale continuous process to- date has produced a material that is more difficult to process but expected to afford higher combustion efficiency. Evaluation of these materials in combination with P-BEP/TVOPA binders was hampered by difficulties in achieving reproducible cure. These difficulties were overcome by...

Topics: DTIC Archive, Baumgartner, W. E., LOCKHEED PROPULSION CO REDLANDS CA, *HYDRIDES, *ALUMINUM...

Ballistic and mechanical properties of a representative NF propellant (RH-SE-103) are being evaluated in a 6-inch motor designed to have many of the characteristics required for a tactical application. A coned-cylindrical grain geometry was substituted for the original slotted-tube configuration on the basis of improved specific-impulse efficiency and low-temperature capability. The coned-cylindrical geometry was fired successfully at temperatures of -31 F, +77 F, and +135 F. The temperature...

Topics: DTIC Archive, Anderson,Stanley E, ROHM AND HAAS CO HUNTSVILLE ALA REDSTONE RESEARCH LABS, *NITROGEN...

Research was carried out to develop, on the basis of direct measurements, mathematical models suit able for describing the propagation of a compression shock wave through soils-principally through partly saturated clays. This interim report deals with the selection of a suitable type of laboratory test and with the design, calibration, and use of gages to measure stress and strain in the vicinity of a point during the propagation of a shock wave. Preliminary results from tests on samples of...

Topics: DTIC Archive, Leonards, G A, PURDUE UNIV LAFAYETTE IN, *SHOCK WAVES, *STRAIN(MECHANICS), *SOILS,...

Theoretical and experimental statistical analysis of the random response of a continuous bar in tension is presented. Particular attention has been paid to the probability distribution of the strain response which, for a linear second-order system under gaussian excitation, follows a Rayleigh distribution. However, when the excitation level of the clamped-clamped continuous bar is sufficiently high so that the tensile strain becomes comparable with the bending strain, then the strain crest...

Topics: DTIC Archive, Smith, D A, MINNESOTA UNIV MINNEAPOLIS, *STRAIN(MECHANICS), *BENDING STRESS,...

The purpose of the tests performed in the high speed wind tunnel was to obtain force data to evaluate the static stability characteristics of the SLV-1B with 4-square-foot fins. The model was instrumented with a six- component internal strain gage balance and two base pressure probes to determine the forces on the model. The model was then placed in the tunnel and tested in the Mach number range of 0.6 through 5.0, and a Reynolds number range of 6 million/ft. to 20 million/ft. The model...

Topics: DTIC Archive, Ziegler, C E, CHANCE VOUGHT CORP DALLAS TX, *SPACECRAFT, *LAUNCH VEHICLES,...

Diamonds of both type I and type IIb were studied by X-ray diffraction microscopy. Long range strain fields are the dominating imperfections in the former, and dislocations appear to be closely related to strain centers. The latter show a much higher density of edge dislocations with Burgers vectors in the (111) planes. These studies corroborate the general view that type I diamond is more perfect but also more strained and type II close to mosaic and less strained. The new findings are...

Topics: DTIC Archive, Euler, F, AIR FORCE CAMBRIDGE RESEARCH LABS HANSCOM AFB MA, *X RAY DIFFRACTION,...

Two methods for measuring tailplane loads have been tested in flight on a Hunter F.2 aircraft. One method used modified tailplane mountings which provided a satisfactory means of checking, in flight, the datums of their strain gauge bridges. Although hysteresis and other non linearities in the load calibrations, together with fairly rapid temperature drift, limited the measuring system's usefulness in the flight tests, it appears that, with refinements in de sign, it should offer a good method...

Topics: DTIC Archive, Nicholas, O P, ROYAL AIRCRAFT ESTABLISHMENT BEDFORD (UNITED KINGDOM), *STRAIN GAGES,...

A study is made of stresses in the vicinity of discontinuities in filaments in filament-reinforced, composite materials. Formulas are derived for the calculation of local stresses in filament or binder, and for the shear stresses induced between them. Sample calculations (in both elastic and plastic stress ranges) show that disturbances from the general stress level are primarily local, near the discontinuity, and particularly that the shear stress between fiber and binder is apt to rise to a...

Topics: DTIC Archive, Dow, Norris F, GENERAL ELECTRIC CO SANTA BARBARA CA, *STRESSES, ALUMINUM COMPOUNDS,...

After reviewing present work in failure criteria for various stress states, this report presents both an analytical and theoretical study of triaxial failure of polymeric materials. The configuration chosen for the investigation is a thin, circular, disk-like specimen that is bonded between rigid, cylindrical bars and pulled parallel to its longitudinal axis. Using the minimumtial energy principle, a stability criterion for catastrophic fracture for spherical voids is made, including details of...

Topics: DTIC Archive, Lindsey, G H, CALIFORNIA INST OF TECH PASADENA GRADUATE AERONAUTICAL LABS,...

Contents: Instrumentation; Test Site; Shear Wave Generation-Test purpose, Experimental procedure, Data analysis, Discussion of results, Conclusions; Characteristic Impedance Coupling-Test purpose, Experimental procedure, Strain, Particle acceleration, Particle velocity, Period data, Crushed zone measurements, Calibration and other data; Correlations and discussion-Particle motion, Energy transfer, Characteristic impedance and particle motion, Particle acceleration.

Topics: DTIC Archive, Nicholls, Harry R, BUREAU OF MINES COLLEGE PARK MD, *SEISMIC WAVES, ACCELERATION,...

Topics: DTIC Archive, GENERAL AMERICAN TRANSPORTATION CORP NILES IL, *ARMOR PLATE, *BODY ARMOR, *LAMINATES,...

Ground motion was observed at six stations between 256- and 784-foot range along a horizontal radius from the Hard Hat nuclear explosion in granite. Primary instrumentation comprised accelerometers oriented to respond to radial motion. Velocity and displacement gages backed up the accelerometers at five stations. At the two most remote stations, accelerometers and velocity gages were installed to respond to three orthogonal components of motion, radial, vertical, and tangential, the latter two...

Topics: DTIC Archive, Perret, William R, SANDIA CORP ALBUQUERQUE NM, *GRANITE, *GROUND MOTION, STRESSES,...

Ground motion prediction formulas based upon elastic wave propagation in one-dimension (no strain transverse to the propagation direction) have been used widely in protective construction work. Actual soil materials exhibit many deviations from elastic behavior. This report assesses the probable influence of these non-elastic effects upon the accuracy of the above-mentioned prediction formulas, and upon the question of stress attenuation with depth. Three different models of soil behavior are...

Topics: DTIC Archive, Whitman, Robert V, MASSACHUSETTS INST OF TECH CAMBRIDGE, *SOIL MECHANICS, ACCURACY,...

Theoretical and experimental work on cratering and penetration is reported. Work is reported in six areas as follows. 1. Energy Partitioning in Impact. Techniques and results are summarized for measurements of target heating, target mass loss, spray energy, and recrystallization and strain energy. 2. Material Properties. The formulation of a general equation describing the relation between pressure, specific volume, and internal energy of a material is reported and the comparison with existing...

Topics: DTIC Archive, Palmer, E P, UTAH UNIV SALT LAKE CITY HIGH VELOCITY LAB, *CRATERING, *PENETRATION,...

The results and findings of researches into stress wave propagation of granular media are presented. The purpose of this work is to clarify air- induced ground shock phenomena in soils, leading to reliable analytical methods of prediction, and to provide guidance for experimental verification and research. This final report summarizes work on one-dimensional wave propagation of bi-linear, locking, and compacting materials, and presents the first results of the extension of these researches into...

Topics: DTIC Archive, Bleich, Hans H, WEIDLINGER ASSOCIATES NEW YORK, *SOIL MECHANICS, *SOILS,...

The tensile behavior of dilute Ta-H and Ta-Mo alloys was studied as a function of alloying addition, grain size and test temperature at a constant strain rate. The results are interpreted in terms of the parameters sigma sub-i and k sub-y of the Petch equation. For Ta-H alloys at 25 C sigma sub-i was independent of hydrogen content whereas k sub-y increased with hydrogen content. Deformation twinning was not observed in Ta-H alloys either at 25 C or at -196 C. Dilute additions of Mo to Ta at 25...

Topics: DTIC Archive, Abowitz, G, MATERIALS RESEARCH CORP ORANGEBURG NY, *TANTALUM ALLOYS, BRITTLENESS,...

The equations are developed for the case of a reverse yielded thick- walled cylinder. It is assumed that a cylinder is subjected to an internal pressure which causes plastic flow throughout the wall; the size of the cylinder is such that the residual stresses developed during pressure release cause the cylinder to reyield in compression. The stress equations for the subsequent reapplication of pressure to the reyielded cylinder are also developed.

Topics: DTIC Archive, Dawson, Victor C D, NAVAL ORDNANCE LAB WHITE OAK MD, *CYLINDRICAL BODIES, *PRESSURE...

In continuation of the work on elastic properties of carbons, using the greatly improved high temperature equipment, families of curves of the dependence of Young's modulus on temperature and on the heat treatment have been obtained for four basic types of carbons and as far as possible, for a number of special types of commercial carbons. The amplitude dependence of internal friction and dynamic Young's modulus were investigated in the sonic range for a number of types of carbons as made and...

Topics: DTIC Archive, Mrozowski, S, STATE UNIV OF NEW YORK AT BUFFALO CARBON RESEARCH LAB, *CARBON,...

SOLID glass or ceramic hulls provide the maximum buoyancy and internal useful volume for underwater vehicles. This material displays low creep characteristics and withstands external pressure cycling and mild underwater dynamic pressures. Scratches on the exterior surfaces do not decrease appreciably the compressive and elastic strength of such vessels when exposed to either static or cycling pressure. Connectors have been devised that enable glass cylinders to be joined into a monolithic...

Topics: DTIC Archive, Stachiw, J D, PENNSYLVANIA STATE UNIV STATE COLLEGE ORDNANCE RESEARCH LAB, *CERAMIC...

The principal uncertainty in the visco-plastic model of hypervelocity impact is the lack of data on strain-rate effects under the severe conditions of interest. Estimates of micron for iron and aluminum are first determined that are compatible both with observed strain-rate effects in plastic waves and the very abrupt shock profiles known to exist at pressures greater than about .2 megabar. In the second part of the report detailed calculations are presented describing the cratering process for...

Topics: DTIC Archive, Riney, T D, GENERAL ELECTRIC CO PHILADELPHIA PA MISSILE AND SPACE DIV, *HYPERVELOCITY...

Sandwich specimens were evaluated that had aluminum facings of various thicknesses and a solid core of Sitka spruce in which a cell of a honeycomb core material was simulated by a round hole. A few tests involving honeycomb cores were made, and results of these were found to agree with those of the other tests for the stress at the start of dimpling of the facings. The maximum stress in the facings of the honeycomb core specimens was lower at failure than for the specimens with wood cores. At...

Topics: DTIC Archive, Norris, C B, FOREST PRODUCTS LAB MADISON WI, *ALUMINUM ALLOYS, *WOOD, *PAPER,...

The work performed during the second contract year was to establish the first year's findings on a firmer basis. This goal has been achieved by tensile strength measurements on Virgin Eand S-glass at approximately the same gage lengths previously used for fibers from E- and S-glass strands. The resulting strength-length curves were similar in shape to the strand fiber curves indicating that mixed flaw populations were present also on freshly drawn fibers, but to varying degrees depending on...

Topics: DTIC Archive, Schmitz, Gunther K, SOLAR TURBINES INTERNATIONAL SAN DIEGO CA, *GLASS TEXTILES,...

The present state of our knowledge on the mechanical behavior of sapphire is reviewed: Sapphire deforms plastically at temperatures above 900 C, the most common mode of deformation being slip on the basal plan in the 1120 direction. However, under certain conditions, slip may occur on prism planes or twinning may occur. A yield point is often observed. This appears to be related to the multiplication of dislocations by a mechaninism which is controlled by the motion of dislocations through the...

Topics: DTIC Archive, Conrad, H, AEROSPACE CORP EL SEGUNDO CA, *SAPPHIRE, *DEFORMATION, CRYSTAL STRUCTURE,...

Viscoelasticity comprises an irreversible relation between stress and strain which is governed by the irreversibility embodied in viscoelasticity which leads to the production of a beneficial residual stress distribution following loading is discussed. Temperature has a marked effect on viscoelastic characteristics, and thus supplies an additional controlling variable in selecting a design solution. Cooling slows down rate processes so that it may be possible to eliminate deleterious aspects of...

Topics: DTIC Archive, Lee, E H, STANFORD UNIV CA DIV OF ENGINEERING MECHANICS, *VISCOELASTICITY, POLYMERS,...

A series of mechanical strength and thermal expansion tests was carried out from room temperature to 5000 F on the two microstructural types of current production pyrolytic graphite. Results indicate that with appropriate precautions in selecting test material, machining and testing specimens, current production pyrolytic graphites yield higher, more reliable mechanical property values. The contribution of process improvements to this increase cannot be specifically separated although it may...

Topics: DTIC Archive, Gebhardt, J J, GENERAL ELECTRIC CO PHILADELPHIA PA MISSILE AND SPACE DIV, *PYROLYTIC...

A numerical method and its machine program for calculating nonlinear viscoelastic wave propagation in soils are described. Solutions give particle velocity, stress and strain as functions of time and distance from the stress source.

Topics: DTIC Archive, Beck, Millicent M, ARMY BALLISTIC RESEARCH LAB ABERDEEN PROVING GROUND MD,...

The mechanical properties of H11 and AISI 4350 steels were determined for a series of bainites formed from both deformed and undeformed austenites. These bainites were also subjected to subsequent straining and tempering treatments. Similar thermomechanical treatments involving martensite as the essential transformation product were included for comparison purposes.

Topics: DTIC Archive, Kalish, D, MANLABS INC CAMBRIDGE MA, *THERMOMECHANICS, *STEEL, *BAINITE,...

The purpose of this investigation was to obtain a better understanding of some of the variables which may affect the properties of HY-80 steel. The data indicate that harden ability is increased with plate thickness. Generally, plates above 3-in. thick contain less than 80 percent martensite. As the percent martensite decreases, so do the Charpy V-notch impact values at -120 F. HY-80 steel made under military specifications MIL-S-16216E and F had lower phosphorous and sulphur content than the...

Topics: DTIC Archive, Willner, A R, DAVID TAYLOR MODEL BASIN WASHINGTON DC, *SUBMARINE HULLS, SHIP PLATES,...

An analysis of creep rupture of ductile materials subjected to strain hardening creep is presented. The analysis is similar to an earlier one by Hoff, but is based on a different generalization of the primary creep rate relation. Both approaches are then extended to time hardening creep. Simple approximate formulae for critical times are presented and the results of both approaches for the two types of creep are compared. Correlation with experimental data for some aluminum-copper,...

Topics: DTIC Archive, Singer, Josef, STANFORD UNIV CA DEPT OF AERONAUTICS AND ASTRONAUTICS, *RUPTURE,...

This study treats the effect of the interaction between underground structures and the surrounding soil in reducing the loads transmitted to the structure, the so-called arching phenomenon. A continuum theory of soils proposed by G. A. Geniev is applied to a quasi-static, planestrain problem of arching. The basic partial differential equations are shown to form a hyperbolic set and are solved by the method of characteristics. Consistent stress and velocity fields are obtained. Comparison with...

Topics: DTIC Archive, Bedesem, W B, ILLINOIS UNIV AT URBANA, *SEISMIC WAVES, *ATTENUATION, *UNDERGROUND...

The effect of mechanical and chemical processing variables on the fracture toughness of adhesive joints was investigated. Two adhesive systems were used. Most of the studies were made on aluminum adherends although some data were collected on steel and glass adherends as well. Fracture toughness was markedly influenced by the chemical variables, which included epoxy system, ratio of epoxy to hardener, and post-cure temperature. The toughness of one epoxy increased with post-cure temperatures up...

Topics: DTIC Archive, Ripling, E J, MATERIALS RESEARCH LAB INC RICHTON PARK IL, *BONDED JOINTS, *TENSILE...

The severe embrittlement caused by a suitable history of strain and temperature has been confirmed for steel conforming to ABS-B classification. Steel prestrained in compression by about 50% at 70 F and subsequently tested in tension fractures at an extensional strain of the order of 1%. Prestraining at 500 F by even 25% causes brittleness in extension at -16 F. Local severe embrittlement of this nature has been shown to be the basic cause of the static initiation of brittle failure of...

Topics: DTIC Archive, Mylonas, C, BROWN UNIV PROVIDENCE RI, *SHIP PLATES, BIBLIOGRAPHIES, TEST METHODS,...

The photoelastic properties of polyvinyl chloride (PVC) were subjected to preliminary investigation several years ago. Some of these measurements were repeated and extended during the past year. These measurements confirm previous observations and demonstrate the contribution of both distortional and orientational contributions to the birefringence. They also indicate the possibility of dichroism studies on partly decomposed PVC which will be described in a future report. Measurements of...

Topics: DTIC Archive, Stein, Richard S, MASSACHUSETTS UNIV AMHERST POLYMER RESEARCH INST, *POLYVINYL...

Destructive dynamic load tests conducted on specimens of copper- nickel pipe joined to bronze couplings by Grade II silver-braze alloy bonds. The bond areas varied from 9 to 85% of the total surfaces available for bonding. Every failure occurred in the bond. Cracking of the coupling sometimes accompanied bond failure. In no case was there rupture of the pipe. Since many joint failures apparently were influenced by a coupling geometry with abrupt changes in cross section, a modified coupling...

Topics: DTIC Archive, Zilliacus, Stephen, DAVID TAYLOR MODEL BASIN WASHINGTON DC, *JOINTS, *SILVER SOLDERS,...

The strength of E- and S-glass fibers was investigated by tensile tests and static fatigue (constant load) tests. The principal variables were: gage length, strain rate, applied stress in static fatigue, and humidity. The gage length study led to identification of two types of surface flaws and a structural flaw type related to the heterogeneity of the glass network. Severity and distribution of flaws were derived from failure probability plots and strength-length plots at one strain rate in...

Topics: DTIC Archive, Schmitz, Gunther K, SOLAR TURBINES INTERNATIONAL SAN DIEGO CA, *CERAMIC FIBERS,...

Test methods, developed during the first year of this program and described in ASD-TDR-63-264, Part I, were used to evaluate the high-temperature capabilities of candidate lubricants intended for use in the advanced gas turbine engines of the commercial supersonic transport. The candidate lubricants were evaluated in the following tests: (1) lubricant oxidationcorrosion test, (2) lubricant deposits and degradation test, and (3) gear load-carrying capacity test. In addition, preliminary tests...

Topics: DTIC Archive, Baber, B B, SOUTHWEST RESEARCH INST SAN ANTONIO TX, *TEST METHODS, EXPERIMENTAL DATA,...

A continuum model of crack extension is used to derive a crack propagation law for the case of constant plastic strain amplitude fatigue. The rate of crack growth is found to be proportional to the square root of the crack length. Integration over the total number of cycles to failure, N sub f, yields an expression of the form N sub f(delta epsilon sub p bar to the n+1 power = f(delta epsilon sub p bar), where delta epsilon sub p bar is the applied plastic strain range, and f is a function...

Topics: DTIC Archive, Grosskreutz, J C, MIDWEST RESEARCH INST KANSAS CITY MO, *CONTINUUM MECHANICS,...

Approximately 325 quartz resonators have been fabricated or purchased and measured for aging and reliability at 85 C over periods up to 14 months. These have been divided among low frequency (100 to 500 kc), 3 Mc, 10 Mc and 16 Mc resonators and among natural, cultured, and electrolytically swept natural and cultured quartz. Data accumulated by electrical measurements and by visual and x-ray diffraction methods have been analyzed in order to determine mechanisms responsible for the principal...

Topics: DTIC Archive, Belser, R B, GEORGIA INST OF TECH ATLANTA ENGINEERING EXPERIMENT STATION, *QUARTZ...

Work consisted of a study of the strain and thermal characteristics of a Full Bridge strain gage over a temperature range of 600 to 2000 F. The following tests were performed: 1. Measurement of bridge sensitivity factor at room and elevated temperatures. 2. Gage drift at constant temperature. 3. Response of gage to rapid radiant heating. 4. Leakage to ground resistance measurement. 5. Self heating effects. It is shown that: 1. Gage installation by means of flame sprayed material was adequate...

Topics: DTIC Archive, Sokolcwski, Benedict A, HIGH TEMPERATURE INSTRUMENTS CORP PHILADELPHIA PA, *STRAIN...

When external loads or other stress-inducing forces are applied to a composite of fibers embedded in a matrix, internal stresses are set up in each constituent and at the same time complex interactions occur between them. The study of these internal stresses, the internal mechanics of the reactions of the constituents, separately and in concert, to the imposed forces, may be called the micromechanics of fibrous composites. The reasons for theoretical and experimental research in micromechanics...

Topics: DTIC Archive, MATERIALS ADVISORY BOARD (NAS-NRC) WASHINGTON DC, *FIBERS, BIBLIOGRAPHIES, CERAMIC...

In a case-bonded rocket motor the propellant is often subjected to biaxial tensile straining, arising from thermal or pressurisation effects. The behaviour of propellants under biaxial straining differs from that under uniaxial straining, and special biaxial test techniques have to be devised. Plastic propellants have some biaxial characteristics in common with other types of propellant, and other which are peculiar to this type of propellant. An account is given of the way in which biaxial...

Topics: DTIC Archive, Cooke, S, EXPLOSIVES RESEARCH AND DEVELOPMENT ESTABLISHMENT WALTHAM ABBEY (UNITED...

Topics: DTIC Archive, McGinley, J G, JOINT TASK FORCE ONE WASHINGTON DC, *SHIPS, STRESSES, NUCLEAR...