Evolving Phase Boundaries in the Presence of Deformation and Surface Stress

Growth of spinel into alumina

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126317 ◽

1987 ◽

Vol 45 ◽

pp. 294-295

Author(s):

Y. Kouh Simpson ◽

C. B. Carter

Keyword(s):

Misfit Dislocations ◽

Phase Boundaries ◽

Large Rotation ◽

Alumina Phase ◽

Metallic Interfaces ◽

Small Rotation

The structure of spinel/alumina phase boundaries has recently been studied using the selected- area diffraction technique. It has been found that there exist several dominant topotactic relationships; of these, the two most common situations are when the {111} plane of spinel is parallel to either the (0001) plane or the {1120} plane of alumina. In both of these cases, it has been found that there is often a small rotation from exact topotaxy (typically 0° to 2° but with larger rotations possible) which partially eliminates the need for misfit dislocations. This rotation is a special phenomenon that may be unique to non-metallic interfaces such as phase boundaries in ceramics. In this report, a special spinel/alumina interface in which a large rotation from the exact topotaxy exists between the (111) plane of spinel and the (OOOl) plane of alumina is discussed.

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The nucleation of cavities at grain boundaries

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126299 ◽

1987 ◽

Vol 45 ◽

pp. 288-291

Author(s):

P. J. Goodhew

Keyword(s):

Surface Tension ◽

Surface Energy ◽

Grain Boundaries ◽

Radiation Damage ◽

Impurity Concentration ◽

Driving Force ◽

Nucleation And Growth ◽

Phase Boundaries ◽

Cavity Nucleation ◽

Spherical Bubble

Cavity nucleation and growth at grain and phase boundaries is of concern because it can lead to failure during creep and can lead to embrittlement as a result of radiation damage. Two major types of cavity are usually distinguished: The term bubble is applied to a cavity which contains gas at a pressure which is at least sufficient to support the surface tension (2g/r for a spherical bubble of radius r and surface energy g). The term void is generally applied to any cavity which contains less gas than this, but is not necessarily empty of gas. A void would therefore tend to shrink in the absence of any imposed driving force for growth, whereas a bubble would be stable or would tend to grow. It is widely considered that cavity nucleation always requires the presence of one or more gas atoms. However since it is extremely difficult to prepare experimental materials with a gas impurity concentration lower than their eventual cavity concentration there is little to be gained by debating this point.

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CHROMIUM CONCENTRATION IN AND AROUND FERRITE-AUSTENITE PHASE BOUNDARIES IN DUPLEX STAINLESS STEELS

Le Journal de Physique Colloques ◽

10.1051/jphyscol:1989861 ◽

1989 ◽

Vol 50 (C8) ◽

pp. C8-361-C8-364 ◽

Cited By ~ 2

Author(s):

V. J. GADGIL ◽

J. J. SWENS ◽

B. H. KOLSTER

Keyword(s):

Stainless Steels ◽

Chromium Concentration ◽

Austenite Phase ◽

Duplex Stainless Steels ◽

Phase Boundaries

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Coincident observations, with QuikSCAT and ASCAT, of the effects of rain-induced sea surface stress during hurricanes Gustav and Ike

OCEANS 2009 ◽

10.23919/oceans.2009.5422242 ◽

2009 ◽

Author(s):

David E. Weissman ◽

Mark A. Bourassa

Keyword(s):

Surface Stress ◽

Sea Surface

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Propagation and Reflection of Plane Waves in a Rotating Magneto-Elastic Fibre-Reinforced Semi Space with Surface Stress

Mechanics and Mechanical Engineering ◽

10.2478/mme-2018-0074 ◽

2020 ◽

Vol 22 (4) ◽

pp. 939-958

Author(s):

Indrajit Roy ◽

D. P. Acharya ◽

Sourav Acharya

Keyword(s):

Surface Stress ◽

Incident Angle ◽

Plane Waves ◽

Three Dimensional ◽

Elastic Fibre ◽

Amplitude Ratios ◽

Governing Equations ◽

Rotation Surface ◽

Wave Velocities ◽

Magnetic Field Rotation

AbstractThe present paper investigates the propagation of quasi longitudinal (qLD) and quasi transverse (qTD) waves in a magneto elastic fibre-reinforced rotating semi-infinite medium. Reflections of waves from the flat boundary with surface stress have been studied in details. The governing equations have been used to obtain the polynomial characteristic equation from which qLD and qTD wave velocities are found. It is observed that both the wave velocities depend upon the incident angle. After imposing the appropriate boundary conditions including surface stress the resultant amplitude ratios for the total displacements have been obtained. Numerically simulated results have been depicted graphically by displaying two and three dimensional graphs to highlight the influence of magnetic field, rotation, surface stress and fibre-reinforcing nature of the material medium on the propagation and reflection of plane waves.

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Whisker Formation in Copper Electroplating

ISTFA 2011: Conference Proceedings from the 37th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2011p0127 ◽

2011 ◽

Author(s):

Theresa Han ◽

Eunin Cho ◽

Jinwoo Heo ◽

Seoung Jae Lee

Keyword(s):

Copper Sulfate ◽

Surface Stress ◽

Whisker Formation ◽

Printed Wiring Boards ◽

Copper Electroplating ◽

Cu Electroplating ◽

Solution Surface ◽

Dry Film

Abstract In the manufacture of Printed Wiring Boards (PWB), unwelcome structures, such as nodules and whiskers can be formed during copper electroplating with copper sulfate. Copper (Cu) whiskers with lengths of up to a few hundred micrometers can lead to electrical shorts between layers or patterns. In this paper, we document factors that can affect the growth of Cu whiskers; decomposition of additives in the Cu electroplating solution, surface stress, acidic cleaner, and the ingredients of a dry film. Contaminants from outside of the electroplating bath and the ingredients of the dry film were shown as key components in the formation of Cu whiskers.

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