Accession Number:

ADA071438

Title:

Fracture Mechanics and Surface Chemistry Studies of Fatigue Crack Growth in an Aluminum Alloy.

Descriptive Note:

Technical rept.,

Corporate Author:

LEHIGH UNIV BETHLEHEM PA INST OF FRACTURE AND SOLID MECHANICS

Personal Author(s):

• Wei,R. P.
• Pao,P. S.
• Hart,R. G.
• Weir,T. W.
• Simmons,G. W.

Report Date:

1979-04-01

Pagination or Media Count:

36.0

Abstract:

Fracture mechanics and surface chemistry studies were carried out to develop further understanding of the influence of water vapor on fatigue crack growth in aluminum alloys. The room temperature fatigue crack growth response was determined for 2219-T851 aluminum alloy exposed to water vapor at presures from 1 Pa to 30 Pa over a range of stress intensity factors K. Data were also obtained in vacuum and dehumidified argon. The test results showed that, at a frequency of 5 Hz, the rate of crack growth is essentially unaffected by water vapor until a threshold pressure is reached. Above this threshold, the rates increased, reaching a maximum within one order of magnitude increase in vapor pressure. Author

Descriptors:

• *ALUMINUM ALLOYS
• *FRACTURE(MECHANICS)
• METALS
• CORROSION
• EXPERIMENTAL DESIGN
• FRACTOGRAPHY
• CRACK PROPAGATION
• CHEMICAL REACTIONS
• ENVIRONMENTAL TESTS
• FATIGUE(MECHANICS)
• CALIBRATION
• SURFACE CHEMISTRY
• HYDROGEN EMBRITTLEMENT
• WATER VAPOR
• WATER EROSION

Subject Categories:

• Properties of Metals and Alloys
• Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE