Grain Boundary Specific Segregation in Nanocrystalline Fe(Cr)
Abstract
A cross-correlative precession electron diffraction - atom probe tomography investigation of Cr segregation in a Fe(Cr) nanocrystalline alloy was undertaken. Solute segregation was found to be dependent on grain boundary type. The results of which were compared to a hybrid Molecular Dynamics and Monte Carlo simulation that predicted the segregation for special character, low angle, and high angle grain boundaries, as well as the angle of inclination of the grain boundary. It was found that the highest segregation concentration was for the high angle grain boundaries and is explained in terms of clustering driven by the onset of phase separation. For special character boundaries, the highest Gibbsain interfacial excess was predicted at the incoherent Epsilon3 followed by Epsilon9 and Epsilon11 boundaries with negligible segregation to the twin and Epsilon5 boundaries. In addition, the low angle grain boundaries predicted negligible segregation. All of these trends matched well with the experiment. This solute boundary segregation dependency for the special character grain boundaries is explained in terms of excess volume and the energetic distribution of the solute in the boundary.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 06, 2016
- Accession Number
- AD1056991
Entities
People
- Gregory B. Thompson
- Richard L. Martens
- Tyler Kaub
- Xiao-xiang Yu
- Xuyang Zhou
Organizations
- University of Alabama