Relationship of Grain Boundary Structure and Mechanical Properties of Inconel 690
Abstract
Stress corrosion cracking (SCC), failure due to environmentally assisted crack nucleation and propagation, is an important metallurgical problem with impact on current and future designs of ship structural components and nuclear reactors. SCC mechanism is dependent on the microstructure, particularly the grain boundaries, for a given alloy composition. This thesis investigated the relationship between the structural nature and the nanoscale mechanical properties on and near the grain boundaries to identify their role in the resistance to stress corrosion cracking. Inconel 690, an austenitic Ni-alloy, was chosen as the material of interest for its relevance in current applications in the nuclear energy technology. Inherent hardness of the solution annealed Inconel 690 were found to be the same for both the grain boundary and bulk regions, and did not vary with grain boundary type, specifically the 3 and high angle boundaries. These results indicate comparable ease of dislocation mobility and absorption at the different grain boundaries of Inconel 690 when indented at room temperature.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 08, 2009
- Accession Number
- ADA541217
Entities
People
- Joseph J. Marra
Organizations
- Massachusetts Institute of Technology