Impact of Irradiation Damage Recovery During Transportation on the Subsequent Room Temperature Tensile Behavior of Irradiated Zirconium Alloys

Tensile behavior of C fiber reinforced amorphous SiCN ceramic matrix composites (C/SiCN ) were investigated by tensile machine. The microstructure morphologies were observed by scanning electron microscope. The results indicate that the tensile stress-strain curves of C/SiCN composites dispaly typical elastic deformation and cracks propagation stages. The 1500°C pre-sabilization treatment of C/SiCN in vacuum facilitates room temperature tensile stress growth. The higher treated temperature such as 1900°C is yet opposite. The reasons were attributed to thermal stress relaxation of C/SiCN after pre-stabilization treatment in vacuum.

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Experimental study and numerical modelling of the irradiation damage recovery in zirconium alloys

Journal of Nuclear Materials ◽

10.1016/j.jnucmat.2010.06.012 ◽

2010 ◽

Vol 403 (1-3) ◽

pp. 135-146 ◽

Cited By ~ 30

Author(s):

J. Ribis ◽

F. Onimus ◽

J.-L. Béchade ◽

S. Doriot ◽

A. Barbu ◽

...

Keyword(s):

Experimental Study ◽

Numerical Modelling ◽

Zirconium Alloys ◽

Irradiation Damage

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Elevated Temperature Tensile Behavior of Nextel™ 720 Fibers

Materials ◽

10.1115/imece2003-43324 ◽

2003 ◽

Author(s):

D. M. Pai ◽

S. N. Yarmolenko ◽

E. Freeman ◽

L. P. Zawada

Keyword(s):

High Temperature ◽

Elevated Temperature ◽

Room Temperature ◽

Thermal Exposure ◽

Strength Distribution ◽

Tensile Behavior ◽

Beneficial Effects ◽

Elevated Temperature Tensile ◽

Long Duration ◽

Temperature Exposure

The tensile behavior of Nextel 720 fibers at elevated temperature was compared with room temperature results for both bare and monazite-coated fibers. While coated and uncoated fibers have nearly identical tensile strengths and Weibull moduli at room temperature, differences in response were seen at elevated temperature. Coated fibers tested at 1200°C were found to have a 40% drop in strength. Uncoated fibers at high temperature exhibited 55% less strength than at room temperature. However, the tensile strength distribution for uncoated fibers tested at high temperature exhibited two distinct populations, indicating two different failure mechanisms. One population showed a 50% drop while the other showed a 64% drop. The coating was thus found to have a protective effect in terms of short-duration high-temperature exposure. Further, the effect of soaking on strength was investigated by thermally soaking coated and uncoated fibers in air at 1200°C for 100 hours prior to tensile testing at elevated temperature. In this case, the long duration of thermal exposure appeared to eliminate the beneficial effects of the coating. Soaked fibers, both coated and uncoated, were found to have nearly identical strengths at 1200°C—a reduction of about 60%.

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Characterization of neutron irradiation damage in zirconium alloys—an international “round-robin” experiment

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100108970 ◽

1978 ◽

Vol 36 (1) ◽

pp. 366-367

Author(s):

D.O. Northwood ◽

R.W. Gilbert ◽

P.M. Kelly ◽

P.K. Madden ◽

D. Faulkner ◽

...

Keyword(s):

Zirconium Alloys ◽

Round Robin ◽

Irradiation Damage ◽

Exact Nature ◽

Dislocation Loops ◽

The Past ◽

Irradiation Growth ◽

Transmission Electron ◽

International Round

Over the past few years there has been disagreement between laboratories on the exact nature of the damage in irradiated zirconium alloys. The main disagreement has centred on whether or not dislocation loops with c-component Burgers' vectors are formed during the irradiation. Since the presence of c-component loops was required in one of the current theories of irradiation growth and is considered in many other models, it was desirable to clear up this point and others relating to the nature of the damage such as loop size, loop concentration and the nature of the loop population, i.e. vacancy or interstitial. To this end a ‘round-robin’ series of transmission electron microscopy (TEM) examinations of neutron irradiated zirconium alloys was organized and the results are reported herein.The participants in the ‘round-robin’ included laboratories who had previously claimed to have seen evidence for c-component damage. The materials examined included zirconium and Zircaloy-2 irradiated at temperatures from 250-400°C, Table 1, the materials irradiated at 400°C providing samples with dislocation loops large enough to determine the interstitial/vacancy nature by inside/outside contrast techniques.

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A microscopic system for high-resolution electron crystallography

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100136726 ◽

1995 ◽

Vol 53 ◽

pp. 70-71

Author(s):

Y. Fujiyoshi ◽

K. Murata ◽

K. Mitsuoka ◽

T. Hirai ◽

A. Miyazawa ◽

...

Keyword(s):

High Resolution ◽

Structure Analysis ◽

Room Temperature ◽

Point Of View ◽

Irradiation Damage ◽

High Resolution Data ◽

Light Harvesting Complex ◽

Resolution Electron ◽

Structural Point ◽

Resolution Data

High-resolution electron cryo-microscopy is one of good candidate for structure analysis of membrane-protein, and also actually analyzed the structure of membrane-proteins such as bacteriorhodopsin (bR) and plant light-harvesting complex (LHC). By developing an expeditious method for structure analysis up to atomic or near atomic resolution, we would like to interpret a function of protein from the structural point of view. However, there are some difficulties in electron microscopy for structure analysis of protein. Especially, the most serious problems are the specimen damage caused by electron irradiation, the denaturation of biomolecules caused by dehydration and missing high-resolution data on electron micrographs at high-tilted angle.The irradiation damage at 8K has been found to be reduced to 1/20 compared with that at room temperature. We have, therefore, developed a high-resolution electron cryo-microscope and improved it by which images can be recorded with higher resolution than 3 Å at a specimen-stage temperature of 4.2 K, even when the specimen is highly tilted. The highly tilted data are essential for reduction of the missing corn effect.

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