In situ observation of corrosion-enhanced dislocation emission and motion resulting in initiation of stress corrosion cracking
- Univ. of Science Technology, Beijing (China). Dept. of Materials Physics
A special constant deflection device for TEM was used to study the change in dislocation configuration ahead of a crack tip during stress corrosion cracking (XC) of brass in water and of Ti-24Al-11Nb alloy in methanol as well as the initiation of SCC. In situ tensile test in TEM for brass was carried out to compare. The results show that corrosion process itself during SCC can enhance dislocation emission, multiplication and motion as well as a dislocation free zone (DFZ) is formed. When the corrosion--enhanced dislocation emission and motion reaches certain a condition a nanocrack of SCC initiates in the DFZ or from the crack tip. Because of the action of the corrosion solution the nanocrack of SCC propagates into a cleavage or intergranular microcrack rather than blunts into a void like in situ tension in TEM.
- OSTI ID:
- 350073
- Report Number(s):
- CONF-980316--
- Country of Publication:
- United States
- Language:
- English
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