Fracture mechanics approach to estimate fatigue lives of welded lap-shear specimens

Lam, Poh -Sang; Pan, Jwo

doi:10.3970/cmc.2015.046.001

Title: Fracture mechanics approach to estimate fatigue lives of welded lap-shear specimens

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Abstract

A full range of stress intensity factor solutions for a kinked crack with finite length is developed as a function of weld width and the sheet thickness. When used with the main crack solutions (global stress intensity factors) in terms of the applied load and the specimen geometric parameters, the fatigue lived of the kinked crack can be estimated for the laser-welded lap-shear specimens. The predicted curve for the load range-fatigue life passes through the cluster of experimental data and is in good agreement. A classical solution associated with an infinitesimal kink is also employed. Furthermore, its life prediction tends to overestimate the actual fatigue life. In addition, the traditional fatigue life estimation based on structural stress is performed for completeness. As a result, this non-fracture mechanics approach only agrees well with the experimental data under high cyclic load conditions.

Authors:

Lam, Poh -Sang ^[1]; Pan, Jwo ^[2]

Savannah River National Lab., Aiken, SC (United States)
Univ. of Michigan, Ann Arbor, MI (United States)

Publication Date:: Mon Jun 29 00:00:00 EDT 2015

Research Org.:: Savannah River Site (SRS), Aiken, SC (United States)

Sponsoring Org.:: USDOE

OSTI Identifier:: 1345816

Report Number(s):: SRNL-STI-2014-00174
Journal ID: ISSN 1546-2218

Grant/Contract Number:: AC09-08SR22470

Resource Type:: Accepted Manuscript

Journal Name:: Computers, Materials and Continua (Print)

Additional Journal Information:: Journal Name: Computers, Materials and Continua (Print); Journal Volume: 46; Journal Issue: 1; Conference: International Conference on Computational and Experimental Engineering and Sciences (ICCES 2014) , Changwon (South Korea), 12-17 Jun 2014; Journal ID: ISSN 1546-2218

Publisher:: Tech Science Press

Country of Publication:: United States

Language:: English

Subject:: 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 42 ENGINEERING; kinked crack; stress intensity factor; lap-shear; weld; fatigue life; Paris law

Citation Formats


                    Lam, Poh -Sang, and Pan, Jwo. Fracture mechanics approach to estimate fatigue lives of welded lap-shear specimens.  United States: N. p., 2015. 
Web.  doi:10.3970/cmc.2015.046.001.

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                    Lam, Poh -Sang, & Pan, Jwo. Fracture mechanics approach to estimate fatigue lives of welded lap-shear specimens.  United States.  https://doi.org/10.3970/cmc.2015.046.001

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                    Lam, Poh -Sang, and Pan, Jwo. Mon .  
"Fracture mechanics approach to estimate fatigue lives of welded lap-shear specimens".  United States.  https://doi.org/10.3970/cmc.2015.046.001.  https://www.osti.gov/servlets/purl/1345816.

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@article{osti_1345816,

  title        = {Fracture mechanics approach to estimate fatigue lives of welded lap-shear specimens},

  author       = {Lam, Poh -Sang and Pan, Jwo},

  abstractNote = {A full range of stress intensity factor solutions for a kinked crack with finite length is developed as a function of weld width and the sheet thickness. When used with the main crack solutions (global stress intensity factors) in terms of the applied load and the specimen geometric parameters, the fatigue lived of the kinked crack can be estimated for the laser-welded lap-shear specimens. The predicted curve for the load range-fatigue life passes through the cluster of experimental data and is in good agreement. A classical solution associated with an infinitesimal kink is also employed. Furthermore, its life prediction tends to overestimate the actual fatigue life. In addition, the traditional fatigue life estimation based on structural stress is performed for completeness. As a result, this non-fracture mechanics approach only agrees well with the experimental data under high cyclic load conditions.},

  doi          = {10.3970/cmc.2015.046.001},

  journal      = {Computers, Materials and Continua (Print)},

  number       = 1,

  volume       = 46,

  place        = {United States},

  year         = {Mon Jun 29 00:00:00 EDT 2015},

  month        = {Mon Jun 29 00:00:00 EDT 2015}

}

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