Advances in fatigue life prediction methodology for metallic materials

Technical Report · Sat Aug 01 04:00:00 EDT 1992

OSTI ID:7166412

Newman, Jr, J C

The capabilities of a plasticity-induced crack-closure model to predict small- and large-crack growth rates, and in some cases total fatigue life, for four aluminum alloys and three titanium alloys under constant-amplitude, variable-amplitude, and spectrum loading are described. Equations to calculate a cyclic-plastic-zone corrected effective stress-intensity factor range from a cyclic J-integral and crack-closure analysis of large cracks were reviewed. The effective stress-intensity factor range against crack growth rate relations were used in the closure model to predict small- and large-crack growth under variable-amplitude and spectrum loading. Using the closure model and microstructural features, a total fatigue life prediction method is demonstrated for three aluminum alloys under various load histories.

• Research Organization: National Aeronautics and Space Administration, Hampton, VA (United States). Langley Research Center
• OSTI ID: 7166412
• Report Number(s): N-92-34191; NASA-TM--107676; NAS--1.15:107676; CNN: RTOP 505-63-50-04
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360103* -- Metals & Alloys-- Mechanical Properties
ALLOYS
ALUMINIUM ALLOYS
CRACK PROPAGATION
CRACKS
CRYSTAL STRUCTURE
FATIGUE
LIFETIME
MATHEMATICAL MODELS
MECHANICAL PROPERTIES
MICROSTRUCTURE
PLASTICITY
SERVICE LIFE
STRESS INTENSITY FACTORS
TITANIUM ALLOYS