Solute effects on the Σ3 111[11-0] tilt grain boundary in BCC Fe: Grain boundary segregation, stability, and embrittlement

Grain boundary (GB) embrittlement by sulfur in fcc CuΣ5(012)[100] symmetrical tilt grain boundary (STGB) is simulated by first-principles calculations. The surface and grain boundary segregation energies are estimated by progressively placing solute atoms in the potential segregation sites in the boundaries. Based on the calculated segregation energies, the cohesive energy of the grain boundary is evaluated as a function of the sulfur atoms concentration. It is found that, when a two atomic layers’ concentration is attained, the cohesive energy is reduced by one order of magnitude compared to its value for the clean grain boundary.

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Grain boundary segregation in metals

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100130651 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1204-1205

Author(s):

C.L. Briant

Keyword(s):

Fracture Surface ◽

Grain Boundary ◽

Grain Boundaries ◽

Material Properties ◽

Electron Spectroscopy ◽

High Vacuum ◽

Boundary Segregation ◽

Grain Boundary Segregation ◽

Local Concentration ◽

The One

Grain boundary segregation is the process by which solute elements in a material diffuse to the grain boundaries, become trapped there, and increase their local concentration at the boundary over that in the bulk. As a result of this process this local concentration of the segregant at the grain boundary can be many orders of magnitude greater than the bulk concentration of the segregant. The importance of this problem lies in the fact that grain boundary segregation can affect many material properties such as fracture, corrosion, and grain growth.One of the best ways to study grain boundary segregation is with Auger electron spectroscopy. This spectroscopy is an extremely surface sensitive technique. When it is used to study grain boundary segregation the sample must first be fractured intergranularly in the high vacuum spectrometer. This fracture surface is then the one that is analyzed. The development of scanning Auger spectrometers have allowed researchers to first image the fracture surface that is created and then to perform analyses on individual grain boundaries.

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Surface and grain-boundary segregation studied by quantitative AES and XPS

International Journal of Materials Research (formerly Zeitschrift fuer Metallkunde) ◽

10.3139/146.110162 ◽

2009 ◽

Vol 100 (9) ◽

pp. 1167-1172 ◽

Cited By ~ 4

Author(s):

Siegfried Hofmann ◽

Pavel Lejček

Keyword(s):

Grain Boundary ◽

Boundary Segregation ◽

Grain Boundary Segregation

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Revealing the factors influencing grain boundary segregation of P, As in Si: Insights from first-principles

Acta Materialia ◽

10.1016/j.actamat.2019.02.014 ◽

2019 ◽

Vol 168 ◽

pp. 52-62 ◽

Cited By ~ 5

Author(s):

Dongdong Zhao ◽

Yanjun Li

Keyword(s):

Grain Boundary ◽

First Principles ◽

Boundary Segregation ◽

Grain Boundary Segregation ◽

Factors Influencing

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An atom probe tomography study of grain boundary segregation in nanocrystalline Ni-W

MRS Proceedings ◽

10.1557/proc-0903-z03-01 ◽

2005 ◽

Vol 903 ◽

Cited By ~ 2

Author(s):

Andrew Detor ◽

Michael K. Miller ◽

Christopher A. Schuh

Keyword(s):

Grain Boundary ◽

Atom Probe Tomography ◽

Boundary Segregation ◽

Atom Probe ◽

Solute Segregation ◽

Grain Boundary Segregation ◽

Distribution Analysis ◽

Grain Sizes ◽

Composition Fluctuations ◽

20 Nm

AbstractAtom probe tomography is used to observe the solute distribution in electrodeposited nanocrystalline Ni-W alloys with three different grain sizes (3, 10, and 20 nm) and the results are compared with atomistic computer simulations. The presence of grain boundary segregation is confirmed by detailed analysis of composition fluctuations in both experimental and simulated structures, and its extent quantified by a frequency distribution analysis. In contrast to other nanocrystalline alloys, the present Ni-W alloys exhibit only a subtle amount of solute segregation to the intergranular regions. This finding is consistent with quantitative predictions for these alloys based upon a thermodynamic model of grain boundary segregation.

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