The effects of residual macrostresses and microstresses on fatigue crack propagation

Journal Article · Sat Aug 01 04:00:00 EDT 1998 · Metallurgical and Materials Transactions. A, Physical Metallurgy and Materials Science

DOI:https://doi.org/10.1007/s11661-998-0038-9· OSTI ID:651063

Almer, J D; Cohen, J B ^[1]; Winholtz, R A ^[2]

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1. Northwestern Univ., Evanston, IL (United States). Dept. of Materials Science and Engineering
2. Univ. of Missouri, Columbia, MO (United States). Dept. of Mechanical Engineering

The effects of residual microstresses and tensile residual macrostresses on fatigue crack propagation (FCP) are examined in a high-carbon steel. Phase-specific diffraction measurements show that uniaxial deformation and radial cold expansion produce predominantly microstress and tensile macrostress fields, respectively. Microstresses are found to have little effect on FCP rates, while tensile macrostresses increase crack growth rates in a manner that depends systematically on {Delta}K. The increases are partly attributed to crack closure, which was found to be appreciable near the surface of control samples but absent in the presence of tensile residual stresses. Both the {Delta}K dependence and absence of microstress effects were explored by X-ray microbeam measurements around propagating fatigue cracks and found to stem from fading and/or redistribution of residual macrostresses and microstresses during fatigue crack growth.

• Sponsoring Organization: USDOE
• OSTI ID: 651063
• Journal Information: Metallurgical and Materials Transactions. A, Physical Metallurgy and Materials Science, Journal Name: Metallurgical and Materials Transactions. A, Physical Metallurgy and Materials Science Journal Issue: 8 Vol. 29; ISSN MMTAEB; ISSN 1073-5623
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CARBON STEELS
CORRELATIONS
CRACK PROPAGATION
FATIGUE
FRACTURE PROPERTIES
RESIDUAL STRESSES