Les dislocations dans des structures lamellaires (étude au microscope électronique)

Doctorat en Sciencesinfo:eu-repo/semantics/nonPublishe

Les dislocations dans des structures lamellaires (étude au microscope électronique)

Doctorat en Sciencesinfo:eu-repo/semantics/nonPublishe

TEM analysis of near‐coincidence grain boundaries in silicon

High‐precision characterization of grain boundaries with a deviation from the ideal coincidence is presented. The analysis is based on the shift of Kikuchi lines at grain boundaries. The accuracy was controlled using Frank's relationship applied to intrinsic secondary dislocations which accommodate the orientation deviation. An application is presented to coincidences with Σ = 25 and 3 observed in polycrystalline silicon. 1990 Blackwell Science LtdSCOPUS: ar.jFLWNAinfo:eu-repo/semantics/publishe

Effects of creep on the microstructural features of an oxide-dispersion-strengthened superalloy

The effects of high temperature creep on the microstructure and the grain boundaries of the oxide-dispersion-strengthened superalloy MA6000 are investigated by means of transmission electron microscopy. Rafting of the γ′ phase is observed in the elongated grains, whereas in the small non-recrystallized grains γ′ rafting does not occur. Dislocations form networks around γ′ precipitates only in particular areas of the coarse grains where the oxide particles are absent. In the rest of the areas, where oxide dispersion is homogeneous, dislocations are pinned to the hard oxide particles instead of accumulating at γ-γ′ interfaces. Dislocation networks around the γ′ phase are not observed in the small grains. There is no detectable influence of high temperature creep on the grain boundaries of the material. The majority of them are of the small angle type and exhibit a very disordered morphology. Large angle grain boundaries are randomly oriented and they are mainly decorated by chromium carbides. © 1991.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

A Surface Effect Associated with Dislocation Ribbons

A new surface effect associated with extended dislocations, in materials with small stacking-fault energy, and which consists in a widening of the ribbons at the surface, is discussed from a theoretical point of view and illustrated with observations in graphite and molybdenum sulphide. The effect leads to a method for estimating surface energies. The surface energy of graphite as deduced from the widening effect is in fair agreement with the value found by other methods.info:eu-repo/semantics/publishe

On the microstructure of an iron-base ODS alloy

SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Detection of Implanted Ions by X-Ray Emission Analysis in TEM

info:eu-repo/semantics/publishe

Detection of implanted ions by X‐ray emission analysis in TEM

SCOPUS: ar.jinfo:eu-repo/semantics/publishe

The stacking-fault energy in germanium

SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Tem study of twin boundary dislocations in cadmium

SCOPUS: ar.jinfo:eu-repo/semantics/publishe