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Title: Small fatigue crack growth in metallic materials: A model and its application to engineering alloys

Abstract

Characterization of the growth behavior of small fatigue cracks is important for materials used in structurally demanding applications such as aircraft turbine discs and some automotive engine components. Here, we present a general, dislocation-based fracture mechanics approach to predict the growth rate of small fatigue cracks in metallic materials. The applicability of the model to the small fatigue crack growth behavior of four engineering alloys was examined. Small fatigue cracks were initiated and propagated, in a controlled manner, from micronotches fabricated by femtosecond pulsed laser micromachining. The results suggest that a methodology consisting of crack-tip damage accumulation and fracture provides a common framework to estimate the fatigue crack propagation lifetime of structural materials.

Authors:
 [1]
  1. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE)
OSTI Identifier:
932104
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Acta Materialia; Journal Volume: 55
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ALLOYS; CRACK PROPAGATION; FRACTURE MECHANICS; DISLOCATIONS; FATIGUE; SERVICE LIFE; FORECASTING

Citation Formats

Shyam, Amit. Small fatigue crack growth in metallic materials: A model and its application to engineering alloys. United States: N. p., 2007. Web. doi:10.1016/j.actamat.2007.08.022.
Shyam, Amit. Small fatigue crack growth in metallic materials: A model and its application to engineering alloys. United States. doi:10.1016/j.actamat.2007.08.022.
Shyam, Amit. Mon . "Small fatigue crack growth in metallic materials: A model and its application to engineering alloys". United States. doi:10.1016/j.actamat.2007.08.022.
@article{osti_932104,
title = {Small fatigue crack growth in metallic materials: A model and its application to engineering alloys},
author = {Shyam, Amit},
abstractNote = {Characterization of the growth behavior of small fatigue cracks is important for materials used in structurally demanding applications such as aircraft turbine discs and some automotive engine components. Here, we present a general, dislocation-based fracture mechanics approach to predict the growth rate of small fatigue cracks in metallic materials. The applicability of the model to the small fatigue crack growth behavior of four engineering alloys was examined. Small fatigue cracks were initiated and propagated, in a controlled manner, from micronotches fabricated by femtosecond pulsed laser micromachining. The results suggest that a methodology consisting of crack-tip damage accumulation and fracture provides a common framework to estimate the fatigue crack propagation lifetime of structural materials.},
doi = {10.1016/j.actamat.2007.08.022},
journal = {Acta Materialia},
number = ,
volume = 55,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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