Effect of Triple Junctions on Grain Boundary and Grain Growth Kinetics in Aluminium - 10 ppm Magnesium Sheet

The motion and geometry of connected grain boundary systems with triple junctions in aluminium -10 ppm magnesium was investigated in-situ with a special designed SEM heating stage. The results show that triple junctions can have a marked influence on grain boundary motion. The grain area change with annealing time was from a hot stage in the SEM. An analysis of the experimental data reveals that there is no unique relationship between growth rate and the number n of grain sides (Von Neumann-Mullins relation). This is attributed to the effect of triple junction drag on grain growth.

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Grain Growth Kinetics in Microcrystalline Materials

MRS Proceedings ◽

10.1557/proc-343-71 ◽

1994 ◽

Vol 343 ◽

Cited By ~ 3

Author(s):

V. G. Sursaeva

Keyword(s):

Activation Energy ◽

Grain Boundary ◽

Grain Growth ◽

Dark Field ◽

Boundary Mobility ◽

Boundary Motion ◽

Grain Boundary Mobility ◽

Grain Growth Kinetics ◽

Microcrystalline Materials ◽

Grain Boundary Motion

ABSTRACTCertain experimental results are presented concerning grain growth in microcrystalline Ag films. Dark field TEM technique was used for the measurement of grain size, trijunction velocity and grain boundary mobility. We found that the activation energy for trijunction motion is 25.0 kJ/g.atom, and the activation energy for the grain boundary motion is 50.0 kJ/g.atom.

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Stress Assisted Grain Growth in Ultrafine and Nanocrystalline Aluminum Revealed by in-situ TEM

MRS Proceedings ◽

10.1557/proc-1086-u09-04 ◽

2008 ◽

Vol 1086 ◽

Cited By ~ 3

Author(s):

Frederic Mompiou ◽

Marc Legros ◽

Daniel Caillard

Keyword(s):

Grain Boundary ◽

Grain Growth ◽

Dislocation Motion ◽

In Situ Tem ◽

Boundary Motion ◽

Fine Grain ◽

Nanocrystalline Aluminum ◽

Grain Boundary Motion

AbstractIn-situ straining experiments on nanocrystalline (nc) and ultra fine grain (UFG) Aluminum were performed at room and intermediate temperatures. Both materials exhibit significant stress assisted grain growth. The strain induced by grain boundary motion has been measured in UFG Al, and was found to be on the order of a few percents. These results cannot be interpreted solely within the framework of Displacement Shift Complete (DSC) dislocation motion. We propose here that GB motion occurs via both shuffling and secondary DSC dislocation motion.

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Motion of Crystal/Crystal and Crystal/Amorphous Interfaces

MRS Proceedings ◽

10.1557/proc-183-79 ◽

1990 ◽

Vol 183 ◽

Author(s):

J. L. Batstone

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

High Temperature ◽

Grain Boundary ◽

Boundary Motion ◽

High Temperature Annealing ◽

Thermally Activated ◽

Transmission Electron ◽

Grain Boundary Motion

AbstractMotion of ordered twin/matrix interfaces in films of silicon on sapphire occurs during high temperature annealing. This process is shown to be thermally activated and is analogous to grain boundary motion. Motion of amorphous/crystalline interfaces occurs during recrystallization of CoSi2 and NiSi2 from the amorphous phase. In-situ transmission electron microscopy has revealed details of the growth kinetics and interfacial roughness.

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Grain Growth in Al: First Results from a Combined Study of Bulk and In-Situ Experiments Using a Columnar Structured Al Foil

Materials Science Forum ◽

10.4028/www.scientific.net/msf.467-470.935 ◽

2004 ◽

Vol 467-470 ◽

pp. 935-940 ◽

Cited By ~ 4

Author(s):

Sandra Piazolo ◽

Vera G. Sursaeva ◽

David J. Prior

Keyword(s):

Grain Boundary ◽

Grain Growth ◽

Electron Backscatter Diffraction ◽

Boundary Energy ◽

Complete Replacement ◽

Von Neumann ◽

In Situ Experiments ◽

First Results ◽

Backscatter Diffraction

First results from grain growth experiments in a columnar structured Al foil show several interesting features: (a) the grain size distribution remains heterogeneous even after up to 300 min. annealing and (b) the Von Neumann-Mullins relation is not always satisfied. To clarify the underlying reasons for these features, in-situ heating experiments within a Scanning Electron Microscope (SEM) were combined with detailed Electron Backscatter Diffraction (EBSD) analysis. These show that the movement of boundaries can be strongly heterogeneous. For example, the complete replacement of one grain by a neighbouring grain without significant change of the surrounding grain boundary topology is frequently seen. Experiments show that grain boundary energy and/or mobility are anisotropic both with respect to misorientation and orientation of grain boundary plane. Low energy and/or mobility boundaries are commonly low angle boundaries, twin boundaries and boundaries that form traces to a low index plane of at least one of the adjacent grains. As a consequence the Von Neumann-Mullins relation is not always satisfied.

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In Situ EBSP Observations of Recrystallization in Commercial Purity Aluminum

Materials Science Forum ◽

10.4028/www.scientific.net/msf.558-559.223 ◽

2007 ◽

Vol 558-559 ◽

pp. 223-228 ◽

Cited By ~ 2

Author(s):

Katsura Kajihara

Keyword(s):

Grain Boundary ◽

Grain Boundaries ◽

Early Stage ◽

Boundary Motion ◽

Commercial Purity ◽

Solute Content ◽

In Situ Observations ◽

Commercial Purity Aluminum ◽

Grain Boundary Motion

This study presents in-situ EBSP observations of recrystallization in commercial purity aluminum sheets with different concentrations of solutes and different states of precipitation. The in-situ observations demonstrate clearly the behaviors of the nucleation and growth of recrystallized grains, and the movements of grain boundaries at an early stage of recrystallization. The high mobility of grain boundaries neighboring the deformed matrix was generally observed presumably due to strain-induced grain boundaries migration. The grain boundary motion was also found to strongly depend to the solute content level. These in-situ observations provide important evidence to show that the behaviors of grain boundary motion at an early stage of recrystallization leads to the grain size distribution and the curvature of grain boundaries after the primary recrystallization.

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Topological Stability of 2-D Vanishing Grains

MRS Proceedings ◽

10.1557/proc-278-391 ◽

1992 ◽

Vol 278 ◽

Author(s):

V. E. Fradkov ◽

M. E. Glicksman ◽

J. Nordberg ◽

M. Palmer ◽

K. Rajan

Keyword(s):

Computer Simulation ◽

Grain Boundary ◽

Grain Growth ◽

Triple Junctions ◽

Polycrystalline Films ◽

Topological Stability ◽

Von Neumann ◽

Small Grains ◽

The Mean ◽

Boundary Model

AbstractGrain growth in polycrystals occurs by decreasing the total number of grains as a result of the disappearance of small ones. That is why the both the kinetic and topological details of shrinking of small grains are important.In 2-D, “uniform boundary model” assumptions imply the von Neumann-Mullins law, and all grains having less than 6 neighbors tend to shrink. The mean topological class ef vanishing grains was found experimentally to be about 4.3. This result suggests that most vanishing grains are either 4- or 5-sided, not transforming to 3-sided ones.Shrinking of 4- and 5-sided 2-D grains was studied experimentally on transparent, pure SCN, (succinonitrile) polycrystalline films and by direct computer simulation of grain boundary capillary motion together with triple junctions. It was found that the grains which are much smaller than their neighbors are topologically stable.

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