Subnanometer scale study of segregation at grain boundaries in an Fe(Si) alloy

Journal Article · Mon Nov 02 04:00:00 EST 1998 · Acta Materialia

DOI:https://doi.org/10.1016/S1359-6454(98)00262-6· OSTI ID:302352

Krakauer, B W ^[1]; Seidman, D N ^[1]

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1. Northwestern Univ., Evanston, IL (United States). Dept. of Materials Science and Engineering

The Gibbsian interfacial excess of silicon ({Gamma}{sub Si}) was determined, on an atomic scale, for 14 grain boundaries (GBs) in a single-phase Fe-3 at.% Si alloy, using a unique combined atom-probe field-ion microscopy/transmission electron microscopy (APFIM/TEM) approach. The specimens were equilibrated at 823 K for 14.5 or 72.5 h before the analyses. TEM was first employed to determine the five geometric degrees of freedom (DOFs) of each GB: unit rotation axis, c, rotation angle, {theta}, and unit GB plane normal, n. APFIM analyses were then utilized to obtain integral profiles perpendicular to the GB planes and from these profiles {Gamma}{sub Si} was determined for each GB. The values of {Gamma}{sub Si} are displayed in three dimensions as a function of sin({theta}{sub dis}/2) and cos({angle}c,n); {theta}{sub dis} is the disorientation angle. This three-dimensional plot represents {Gamma}{sub Si} as a function of the five macroscopic DOFs and is a direct representation of GB phase space segregation data.

• OSTI ID: 302352
• Journal Information: Acta Materialia, Journal Name: Acta Materialia Journal Issue: 17 Vol. 46; ISSN 1359-6454; ISSN ACMAFD
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
GRAIN BOUNDARIES
GRAIN ORIENTATION
IRON BASE ALLOYS
SEGREGATION
SILICON ALLOYS