A critical analysis of fatigue-crack propagation data for 2024-T3 aluminum.

Fatigue-crack growth data for 2024-T3 aluminum was used to evaluate the accuracy of Forman's equation. Forman's equation was found to predict from one-third to twice the observed cycles to a given crack length when applied to multiple cyclic stress ratios. An alternative approach was developed, based on the observed data, which is applicable to analog or digital fatigue-crack growth prediction. Data acquisition based on constant increment of crack length has been found to yield inadequate definition of the crack-growth curve in the low-cycle range for the successful application of the method. An expression was developed which extends the application of the crack-closure concept to the entire range of cyclic stress ratio. An effective root-mean-square stress was defined which shows indications of good correlation with the magnitude of the crack-growth curves.

Department dc:contributor.department

Aeronautics

Grantor dc:publisher

Monterey, California. Naval Postgraduate School

Year dc:date.issued

1974

Author dc:creator

• Kish, Robert Alan

Advisor dc:contributor.advisor

• Lindsey, G.H.

Statement dc:rights

• This publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. Copyright protection is not available for this work in the United States.

Language dc:language.iso

en_US

Handle dc:identifier.uri

https://hdl.handle.net/10945/16950

OAI identifier oai:identifier

oai:calhoun.nps.edu:10945/16950