Bend stress relaxation and tensile primary creep of a polycrystalline Ü-SiC fiber

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National Aeronautics and Space Administration, National Technical Information Service, distributor , [Washington, D.C, Springfield, Va
Tensile creep., Stress relaxation., Bend tests., Tensile tests., Polycrystals., Reinforcing fibers., Silicon carbides., Ceramic fi
StatementGregory N. Morscher, Hee Man Yun, and Jon C. Goldsby.
SeriesNASA-TM -- 111683., NASA technical memorandum -- 111683.
ContributionsYun, Hee Man., Goldsby, Jon C., United States. National Aeronautics and Space Administration.
The Physical Object
FormatMicroform
Pagination1 v.
ID Numbers
Open LibraryOL15498236M

Figure 1. Schematic representationof bend stress relaxation and bend stress relaxation recover)' experiments. constrained fibers were then subjected to a heat treatment at temperature, T, for 1, 10, or hours in argon. After cooling the fibers were removed from the fixture and the radius of curvature, R_, was Size: KB.

Bend stress relaxation and tensile primary creep of a polycrystalline gas-SiC fiber (SuDoc NAS ) [Morscher, Gregory N.] on *FREE* shipping on qualifying offers. Bend stress relaxation and tensile primary creep of a polycrystalline gas-SiC fiber (SuDoc NAS ). Understanding the thermomechanical behavior (creep and stress relaxation) of ceramic fibers is of both practical and basic interest.

On the practical level, ceramic fibers are the reinforcement for ceramic matrix composites which are being developed for use in high temperature by: 5. In this study, the bend stress relaxation (BSR) method was applied to investigate the creep behavior of advanced SiC-based fibers.

The apparent activation energies of creep were calculated by a cross-cut method from the time–temperature dependence of stress relaxation by: Bend stress relaxation and tensile primary creep of a polycrystalline α-SiC fiber.

[Washington, D.C.: Springfield, Va: National Aeronautics and Space Administration ; National Technical Information Service, distributor.

MLA Citation. Morscher, Gregory N. and Yun, Hee Man. and Goldsby, Jon C. and United States. Three different CVD SiC fibers were tested for bend stress relaxation (BSR) and tensile creep over a wide range of temperatures, times, and stresses.

Tensile Creep and Creep-Recovery Behavior of a S i C- F i be r-Si N,-Mat r i x Corn posi te John W. Holmes,*.' Yong H. Park,' and J. Wayne JonesC Ceramic Composites Research Laboratory, Department of Mechanical Engineering and Applied Mechanics and Department of Materials Science and Engineering, The Liniversity of Michigan, Ann Arbor, Michigan 48 File Size: 1MB.

Fiber integration and manipulation at all stages in Antares applied tensile stress force on smf fiber fabrication (after ITU specifications) radius r 6,25E m graviation 9,81 diameter D 1,25E m conversion 0, cross section A 1,23E m2 1,23E mm2 pressure p 1,00E+05 psi 6,89E+08 Pa (pressure equal to one newton per square meter)File Size: KB.

Below are shown and labeled (by letter) several schematic stress-strain curves that may be displayed by polymeric materials at room temperature.

Indicate, by letter, the stress-strain behavior expected for each of the following polymers. On creep curve of strain versus time, its the part that has a decreasing slope ; material experiences increase in creep resistance or strain hardening Secondary creep On creep curve of strain versus time, its the linear portion of the graph (steady state); the competing balance of strain hardening and recovery from deformation.

the ability to resist stress and is expressed as tensile strength or as tenacity, breaking tenacity is the number of grams of force to break a fiber stretching the process of pulling a fiber so that the molecular chains rotate and slide until they become oriented to form crystals within the fiber to enhance certain fiber properties.

Bend stress relaxation (BSR) tests were performed on a developmental yttrium aluminum garnet (YAG) polycrystalline fiber. The YAG fibers were 15 to 30 microns in diameter and were produced from.

Description Bend stress relaxation and tensile primary creep of a polycrystalline Ü-SiC fiber PDF

G.N. Morscher, H.M. Yun, and J.C. Goldsby, Viscoelastic analysis of bend stress relaxation and tensile primary creep of a polycrystalline α-SiC fiber, Author: James A. DiCarlo, Hee Mann Yun. Elasticity, Stress Relaxation and Creep in SiC Particle Reinforced Oxynitride Glass p Improvement of High Temperature Strength and Creep of α-Sialon by Grain Boundary Crystallization p Creep Processes in the Advanced Silicon Nitride Ceramics p Creep Deformation and Fracture of SiC/SiC Composites Cited by: 4.

To accomplish this, an empirical model is proposed which has been found to phenomenologically describe primary stage tensile creep of SiC polycrystalline fibers as a function of stress, time, and temperature.

This model is then further expanded to include a description of fiber stress Size: 1MB. Get this from a library. Bend stress relaxation and tensile primary creep of a polycrystalline [alpha]-SiC fiber. [Gregory N Morscher; Hee Mann Yun; Jon C Goldsby; United States.

National Aeronautics and Space Administration.]. Buy Bend stress relaxation and tensile primary creep of a polycrystalline gas-SiC fiber (SuDoc NAS ) by Gregory N. Morscher (ISBN:) from Amazon's Book Store. Everyday low prices and free delivery on eligible : Gregory N.

Morscher.

Details Bend stress relaxation and tensile primary creep of a polycrystalline Ü-SiC fiber PDF

Journal Article: Comparison of bend stress relaxation and tensile creep of CVD SiC fibers. At the low stress regime, however, significant improvement on the creep resistance was observed in the composite material over the monolithic alloy.

The improved creep resistance is accompanied by an increase of the stress exponent from to for the monolithic alloy to a value of – for the composite material. For example, at room temperature, the creep rate of.

the polyester laminate in tension at 0° to warp at 30, pounds per square inch. for hours would be x 10 -6 inch per inch per hour, compared to x. 10 -6 inch per inch per hour for the epoxy laminate. Time/temperature dependent tensile strength of SiC and Al₂O₃-based fibers.

[Washington, D.C.: Springfield, Va: National Aeronautics and Space Administration ; National Technical Information Service, distributor. MLA Citation. Yun, Hee Mann. and DiCarlo, James A.

and United States. National Aeronautics and Space Administration. fiber fibers properties sic tensile fracture grain creep hnl steels hnls ionomers composite polymer mpa biolox magnetic oxidation matrix oxygen diameter delta You can write a book review and share your experiences. Other readers will.

This proceedings volume, "Plastic Deformation of Ceramics," constitutes the papers of an international symposium held at Snowbird, Utah from AugustIt was attended by nearly scientists and engineers from more than a dozen countries representing academia, national laboratories, and.

The stress relaxation over a fixed time was found to be proportional to the stress when growth was terminated and the effect of temperature was found to be very weak. These results suggest that grain-boundary diffusion is not a factor in the stress relaxation.

DOI: /PhysRevB PACS number s: a, i, Gy, Bk. A simple bend stress relaxation (BSR) test has been used to measure the creep related properties of a chemically vapor-deposited SiC fiber. Time, temperature, and strain dependent BSR data were analyzed to ascertain the ability of the stress relaxation results to predict tensile creep as a function.

planes, directions, polycrystalline plastic deformation II. Stress versus Strain Curves for Polymers in Uniaxial Tension along tensile axis, void formation, stress whitening 5)2nd strain hardening regim: recrystallization to a fiber like oriented structure, high stiffness s, e s, e.

Comparison of Amorphous andFile Size: 9MB. Tensile Creep Fracture of Polycrystalline Near-Stoichiometric Nial [Raj, Sai V., Nasa Technical Reports Server (Ntrs)] on *FREE* shipping on qualifying offers.

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Tensile Creep Fracture of Polycrystalline Near-Stoichiometric NialCited by: 1. processes typically needed for some CMC products. As described here, the new Sylramic-iBN fiber type with an in-situ grown BN layer goes a long way in this direction, as well as providing most of the other key properties needed for the fiber reinforcement of high-temperature SiC/SiC composites REFERENCES 1.

J.A. DiCarlo and S. Dutta, Continuous Ceramic Fibers for. Engineering Science Aspects of the Hall-Petch Relation* Ronald W. Armstrong. stress-strain behavior of a polycrystalline aluminum material and that of a single crystal obtain the polycrystal flow stress, σε, and to divide into the resolved shear strain, γ, to obtain the polycrystal tensile strain, ε.

File Size: KB. Design with Plastics* *Adapted from G.G. Trantina, “Design with Plastics,” Materials Selection and Design, Vol ASM Handbook, ASM International,pages to THE KEY to any successful part develop-ment is the proper choice of material, process.

Examples include (1) the use of this technique for high-resolution stress mapping and stress profiling in thin films and coatings, (2) strain mapping in MEMS and TSV structures, (3) the analysis of residual stress distribution inside single grains (or across GBs) in polycrystalline materials, (4) the investigation on stress concentration and/or Cited by: The physical characteristics, fabrication methods, and key microstructural features of all ceramic fibers, both oxides and non-oxides, are tabulated in Table The characteristics of fibers that are commercially available are summarized in Tableincluding maximum use temperature, current uses, and current c oxide fibers (often referred to as oxide fibers) are composed .Bend stress relaxation of Al 2 O 3-YAG eutectic fibers.

Ceramic Engineering and Science Proceedings 16(5): – Ceramic Engineering and Science Proceedings 16(5): – Morscher, G.N., D. Bryant, and R.E. Tressler.