The Interaction of Dimensional Changes and Irradiation Creep in Reactor Graphite

When graphite is irradiated by fast neutrons, damage to the crystal structure causes changes of the graphite dimensions. In the graphite blocks comprising the core of a nuclear reactor, there are differential dimensional changes, thus stresses are developed, analogous to thermal stresses in a body in which there are spatial variations of temperature. The stresses are partially relaxed by an irradiation-induced creep of the graphite. In this paper the authors present a method of predicting the stresses which makes allowance for the relaxation by irradiation creep.

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Criteria for the evaluation of low-temperature Scanning Electron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100145820 ◽

1986 ◽

Vol 44 ◽

pp. 902-903

Author(s):

Alan Beckett

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Low Temperature ◽

Conformational Changes ◽

Chemical Vapour ◽

List Type ◽

Dimensional Changes ◽

Critical Point Drying ◽

Temperature Scanning ◽

Scanning Electron

Low temperature scanning electron microscopy (LTSEM) has been evaluated with special reference to its application to the study of morphology and development in microorganisms. A number of criteria have been considered and have proved valuable in assessing the standard of results achieved. To further aid our understanding of these results, it has been necessary to compare those obtained by LTSEM with those from more conventional preparatory procedures such as 1) chemical fixation, dehydration and critical point-drying; 2) freeze-drying with or without chemical vapour fixation before hand.The criteria used for assessing LTSEM for the above purposes are as follows: 1)Specimen immobilization and stabilization2)General preservation of external morphology3)General preservation of internal morphology4)Exposure to solvents5)Overall dimensional changes6)Cell surface texture7)Differential conformational changes8)Etching frozen-hydrated material9)Beam damage10)Specimen resolution11)Specimen life

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Alveolar ridge dimensional changes after two socket sealing techniques. A randomized clinical trial

10.26226/morressier.5ac3831d2afeeb00097a3991 ◽

2018 ◽

Author(s):

Maxim Debel

Keyword(s):

Clinical Trial ◽

Randomized Clinical Trial ◽

Alveolar Ridge ◽

Dimensional Changes

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INVAR

Alloy Digest ◽

10.31399/asm.ad.fe0024 ◽

1964 ◽

Vol 13 (3) ◽

Keyword(s):

Corrosion Resistance ◽

High Temperature ◽

Physical Properties ◽

Iron Alloy ◽

Heat Treating ◽

Temperature Variations ◽

Nickel Iron ◽

Dimensional Changes ◽

Temperature Performance ◽

Nickel Iron Alloy

Abstract INVAR is a 36% nickel-iron alloy having the lowest coefficient of expansion, recommended for applications requiring no dimensional changes with temperature variations. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on low and high temperature performance, and corrosion resistance as well as forming, heat treating, machining, joining, and surface treatment. Filing Code: Fe-24. Producer or source: Carpenter.

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DEUTSCHE EDELSTAHLWERKE CRYODUR 2067

Alloy Digest ◽

10.31399/asm.ad.ts0786 ◽

2020 ◽

Vol 69 (2) ◽

Keyword(s):

Cold Work ◽

High Surface ◽

Surface Hardness ◽

Heat Treating ◽

Chromium Alloy ◽

Dimensional Changes ◽

Short Run ◽

Quench Hardening ◽

Specialty Steel ◽

Cold Work Tool Steel

Abstract Deutsche Edelstahlwerke Cryodur 2067 is a high-carbon, 1.5% chromium, alloy cold-work tool steel. In view of its higher hardenability than that of the non-alloy, water-hardening, cold work tool steels, this steel can be oil quenched, a factor that minimizes dimensional changes during quench hardening. Cryodur 2067 is suitable for short run tooling in applications requiring high surface hardness. This datasheet provides information on composition, physical properties, hardness, and elasticity. It also includes information on forming, heat treating, and machining. Filing Code: TS-786. Producer or source: Deutsche Edelstahlwerke Specialty Steel.

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