Accession Number:

ADA109890

Title:

The Plastic Zone and Residual Stress near a Notch and a Fatigue Crack in HSLA Steel.

Descriptive Note:

Technical rept.,

Corporate Author:

NORTHWESTERN UNIV EVANSTON IL DEPT OF MATERIALS SCIENCE

Personal Author(s):

• Schlosberg,W. H.
• Cohen,J. B.

Report Date:

1981-12-16

Pagination or Media Count:

55.0

Abstract:

The plastic zone and residual stress around a notch under load and with the load removed, and around a fatigue crack at the same stress intensity factor as for the notch have been examined, with automated X-ray techniques and a microbeam. There is a good agreement between the measured plastic zone size and Hutchinsons theory for a work hardening material. Residual stresses exist well behind the tip, and vary with depth, so that measurements of crack closure on a surface may not be directly related to closure stress which samples the bulk. Instabilities in the dislocation arrangement can be detected by comparing X-ray line broadening of bulk specimens under load, and with the load removed. Author

Descriptors:

• *PLASTIC DEFORMATION
• *STEEL
• *CRACK PROPAGATION
• *RESIDUAL STRESS
• *FATIGUE(MECHANICS)
• MEASUREMENT
• MICROSTRUCTURE
• NONDESTRUCTIVE TESTING
• LOADS(FORCES)
• ELASTIC PROPERTIES
• TEST METHODS
• X RAYS
• EQUATIONS
• HARDENING
• NOTCH TOUGHNESS
• LINEAR ALGEBRA
• MICROBEAMS

Subject Categories:

• Properties of Metals and Alloys
• Test Facilities, Equipment and Methods
• Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE