In situ observation of corrosion-enhanced dislocation emission and motion resulting in initiation of stress corrosion cracking

Chu, W Y; Gu, B; Gao, K W; Zhang, T C; Hsiao, C M

Title: In situ observation of corrosion-enhanced dislocation emission and motion resulting in initiation of stress corrosion cracking

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Abstract

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.

Authors:

Chu, W Y; Gu, B; Gao, K W; Zhang, T C; Hsiao, C M ^[1]

Univ. of Science Technology, Beijing (China). Dept. of Materials Physics

Publication Date:: Thu Dec 31 00:00:00 EST 1998

OSTI Identifier:: 350073

Report Number(s):: CONF-980316-
TRN: IM9925%%421

Resource Type:: Conference

Resource Relation:: Conference: Corrosion `98, San Diego, CA (United States), 22-27 Mar 1998; Other Information: PBD: 1998; Related Information: Is Part Of Corrosion `98: 53. annual conference and exposition, proceedings; PB: [6600] p.

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE; CRACK PROPAGATION; STRESS CORROSION; BRASS; TITANIUM BASE ALLOYS; ALUMINIUM ALLOYS; NIOBIUM ALLOYS; METHANOL; WATER; CORROSIVE EFFECTS; DISLOCATIONS

Citation Formats


                    Chu, W Y, Gu, B, Gao, K W, Zhang, T C, and Hsiao, C M. In situ observation of corrosion-enhanced dislocation emission and motion resulting in initiation of stress corrosion cracking.  United States: N. p., 1998. 
        Web.

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                    Chu, W Y, Gu, B, Gao, K W, Zhang, T C, & Hsiao, C M. In situ observation of corrosion-enhanced dislocation emission and motion resulting in initiation of stress corrosion cracking.  United States.

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                    Chu, W Y, Gu, B, Gao, K W, Zhang, T C, and Hsiao, C M. 1998.  
        "In situ observation of corrosion-enhanced dislocation emission and motion resulting in initiation of stress corrosion cracking".  United States.

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@article{osti_350073,

  title        = {In situ observation of corrosion-enhanced dislocation emission and motion resulting in initiation of stress corrosion cracking},

  author       = {Chu, W Y and Gu, B and Gao, K W and Zhang, T C and Hsiao, C M},

  abstractNote = {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.},

  doi          = {},

  url          = {https://www.osti.gov/biblio/350073},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {Thu Dec 31 00:00:00 EST 1998},

  month        = {Thu Dec 31 00:00:00 EST 1998}

}

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