Public Abstract

DE-SC0016306: Collaborative Research: The Role of Grain Boundary Structure and Chemistry in Materials Failure

Award Status: Inactive

Institution: Arizona Board of Regents, The University of Arizona, Tucson, AZ
UEI: ED44Y3W6P7B9
DUNS: 806345617

Most Recent Award Date: 04/26/2017
Number of Support Periods: 1
PM: Vetrano, John

Current Budget Period: 07/15/2016 - 07/14/2017
Current Project Period: 07/15/2016 - 07/14/2017
PI: Aifantis, Katerina

Supplement Budget Period: N/A

Public Abstract

Macroscopic mechanical testing has revealed that chemical segregation at grain boundaries results in a change of the Hall-Petch slope, indicating a change in grain boundary strengthening due to the presence of solute atoms. The project will study the role of chemical segregation on the local yielding of grain boundaries using nano-indentation and in situ transmission electron microscopy to isolate the segregation effect on dislocation-boundary interaction. In the case of segregation induced grain boundary strengthening the experimental results will be considered within a macroscopic framework that the grain boundary energy increases with plastic strain using the atomistic hypothesis that the initial grain boundary deformation causes a disruption of the lowest energy solute atom configuration.

Macroscopic mechanical testing has revealed that chemical segregation at grain boundaries results in a change of the Hall-Petch slope, indicating a change in grain boundary strengthening due to the presence of solute atoms. The project will study the role of chemical segregation on the local yielding of grain boundaries using nano-indentation and in situ transmission electron microscopy to isolate the segregation effect on dislocation-boundary interaction. In the case of segregation induced grain boundary strengthening the experimental results will be considered within a macroscopic framework that the grain boundary energy increases with plastic strain using the atomistic hypothesis that the initial grain boundary deformation causes a disruption of the lowest energy solute atom configuration.