Abstract
Cavities are examined in a 12Cr0.36Ta steel specimen crept at 650 °C/130 MPa employing three-dimensional (3D) electron backscatter diffraction (EBSD) technique. Observation revealed that cavities are formed at the junctions where high angle grain boundaries (HAGBs) and low angle grain boundaries (LAGBs) coincide. Activation energies required for cavity formation at the junctions of four and three grains/subgrains are lower compared to nucleation in the bulk. This makes four and three grain/subgrain junctions prone to creep cavitation. Cavities have grown towards the highly misoriented grains. 3D reconstruction revealed that cavities are interconnected in reality that cannot be visualized from the two-dimensional (2D) investigations. At moderate stress level, as in present situation cavities have disc type morphology.
Original language | English |
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Pages (from-to) | 76-79 |
Number of pages | 4 |
Journal | Materials Letters |
Volume | 207 |
DOIs | |
Publication status | Published - 15 Nov 2017 |
Keywords
- Cavities
- Creep
- Deformation and fracture
- Electron microscopy
- Grain boundaries
- Microstructure
ASJC Scopus subject areas
- Materials Science(all)
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering