Author: J. A. HenkenerPublisher:
ISBN:
Category : Beryllium
Languages : en
Pages : 64
Book Description
The Mechanical Behavior of Cross-rolled Beryllium Sheet
Author: J. A. HenkenerPublisher:
ISBN:
Category : Beryllium
Languages : en
Pages : 64
Book Description
The Mechanical Behavior of Cross-Rolled Beryllium Sheet
Author: National Aeronautics and Space Administration (NASA)Publisher: Createspace Independent Publishing Platform
ISBN: 9781722817046
Category :
Languages : en
Pages : 62
Book Description
In response to the failure of a conical section of the Insat C satellite during certification testing, the use of beryllium for payload structures, particularly in sheet product form, is being reevaluated. A test program was initiated to study the tensile, shear, and out-of-plane failure modes of beryllium cross-rolled sheet and to apply data to the development of an appropriate failure criterion. Tensile test results indicated that sanding the surface of beryllium sheet has no significant effect on yield strength but can produce a profound reduction in ultimate strength and results obtained by finite element analysis. Critical examination of these test results may contribute to the modification of a JSC policy for the use of beryllium in orbiter and payload structures. Henkener, J. A. and Spiker, I. K. and Castner, W. L. Johnson Space Center...
Test Methods for Mechanical Properties of Anisotropic Materials (Beryllium Sheet)
Author: Raymond W. Fenn (Jr)Publisher:
ISBN:
Category : Anisotropy
Languages : en
Pages : 168
Book Description
Test techniques were developed for the determination of short-transverse tensile properties, Poisson's ratios, and shear moduli in anisotropic sheet. Cross-rolled 0.077-in. thick S-200 Beryllium sheet was tested to determine Young's moduli, Poisson's ratios, shear moduli, uniaxial tensile properties in three directions, biaxial tensile properties, three- and four-pint bend characteristics, fracture toughness, effect of anisotropy on fatigue strength, microstructural characteristics, basal and prism pole figures.
Structural Response of Beryllium Sheet Produced by Three Fabrication Methods
Author: C. J. GiemzaPublisher:
ISBN:
Category : Beryllium
Languages : en
Pages : 62
Book Description
Hot-pressed, hot-upset and hot cross-rolled Be sheets were examined to assess their differences and advantages from a structural design viewpoint. Tension, notch tension, compression, bend ductility and box-beam tests, with the main emphasis on factors which tend to embrittle Be, were conducted. The results showed that hot cross-rolled Be sheet exhibited both high strength and high elongation in tensile tests but was relatively brittle when, as in bending, the stress was complex. Hot-pressed Be sheet, which was low in tensile strength and elongation, demonstrated an excellent capacity for accommodating complex stresses in bending without fracture. The hot-upset Be sheet exhibited the best characteristics possessed by both hot-pressed and hot cross-rolled Be, though to a lesser degree than the optimum of each. The differences in mechanical behavior among the 3 groups were apparently a function of the degree of preferred orientation. However, the amounts of impurity elements which were reported could have contributed significantly to the embrittlement of the hot- pressed and hot cross-rolled Be sheet.
Preliminary Attempts to Produce Randomly Oriented Wrought Beryllium and Their Relation to Texture Development
Author: F. M. YansPublisher:
ISBN:
Category : Beryllium
Languages : en
Pages : 60
Book Description
Several experiments were performed utilizing beryllium single crystals and polycrystalline material in an effort to produce randomly oriented wrought beryllium and to relate the deformation modes to texture development during plastic deformation.
Physical Metallurgy of Beryllium
Author: H. D. HanesPublisher:
ISBN:
Category : Beryllium
Languages : en
Pages : 56
Book Description
This report summarizes the recent work done to more fully understand the physical metallurgy of beryllium. A review of work on purification of beryllium, which has yielded high-quality single crystals, was made. The basic deformation properties of beryllium have thus been more clearly defined. The effects of certain alloying elements and impurities are also discussed. Deformation modes in polycrystalline beryllium are discussed based on the results of studies of single crystals. The texture developed in polycrystalline beryllium by fabrication and resulting effects on mechanical properties are dealt with, as well as fracture modes in single-crystal and polycrystalline beryllium. Bend-plane splitting is the method suggested for initiation of fracture in beryllium. Some effects of the distribution of impurities as a result of thermal treatment on the mechanical properties are cited. Since grain size is an important factor in determining properties, recrystallization and grain-growth phenomena are covered. The physical-metallurgical phenomena which contribute to the properties and fabricability of commercial products are discussed. (Author).
Dynamic Behavior of Beryllium as a Function of Texture
Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 5
Book Description
The high-strain-rate stress-strain responses of commercial hot-pressed beryllium and rolled-sheet beryllium were studied as a function of orientation in compression and room temperature. Hot-pressed beryllium exhibits isotropic mechanical properties; whereas 16:1 rolled sheet was highly anisotropic. Rolled sheet displayed a factor of two difference in strength between the thickness and in-plane (lowest) directions. Twinning is a key deformation mechanism at high rates.
Beryllium Ingot Sheet
Author: Stanley W. PorembkaPublisher:
ISBN:
Category : Beryllium
Languages : en
Pages : 14
Book Description
This memorandum deals with the fabrication of beryllium ingot sheet. Until recently, most beryllium products have been fabricated from hot-pressed powder materials. As a result of the development of sound castings of beryllium of sufficient size, beryllium ingot sheet can now be made. The greatest advantage of sheet from cast ingots as compared with sheet from pressed powder is increased formability. However, ingot sheet has lower strength, and work is underway to improve the strength without serious loss of fabricability. The purpose of this summary is to review the casting and fabrication procedures for beryllium ingot and the resulting properties of sheet materials. (Author).
Effects of Prestraining Under Hydrostatic Pressure on the Mechanical Behavior of Polycrystalline Beryllium
Author: N. InouePublisher:
ISBN:
Category :
Languages : en
Pages : 104
Book Description
The effects of hydrostatic pressure up to 400 ksi and at 25 C to 300 C on the mechanical properties of three forms of beryllium (hot-pressed block, extruded rod and cross-rolled sheet) were investigated. Three effects of pressure were studied: mechanical behavior under pressure, the effect of pressure cycling on the subsequent atmospheric pressure mechanical properties and the effects of prestraining under hydrostatic pressure on the subsequent atmospheric pressure mechanical properties. Pressure cycling did not produce a significant improvement in the tensile ductility of the hot-pressed and the extruded materials; it did, however, given an improvement in the tensile and bend ductility of the sheet. With the possible exception of an improvement in the bend ductility of sheet, tensile prestraining under hydrostatic pressure either produced no change in the subsequent atmospheric pressure ductility or there resulted a decrease. The prestraining did, however, give an increase in yield and fracture stresses. The results obtained in the present investigation suggest that the principal effect of pressure is on the fracture stress rather than on the flow stress. (Author).
Summary of Beryllium Research and Develpment Programs
Author: A. N. AshurstPublisher:
ISBN:
Category : Beryllium
Languages : en
Pages : 56
Book Description