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KEY TERMS:
NASGRO
FLAGRO
life
assessment
crack
growth
fracture
mechanics
damage
tolerance
structural
integrity
analysis
materials
database
consortium
software
stress
intensity
factor
boundary
element
method
fracture
control
critical
crack size
NASA
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NASGRO® Crack Growth Equation |
The NASGRO crack growth equation accounts for stress ratio effects using a simple crack closure model and also treats the near-threshold and near-instability regions explicitly with multiple parameters.
The user can provide a different crack growth equation or input 1-D or 2-D tabular da/dN vs. ΔK data if desired. The effects of stress ratio and crack size on threshold are also modeled, as well as the changes in toughness for different thicknesses or for surface cracks.
For variable amplitude loading, five different load interaction models are available:
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Generalized Willenborg
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Modified generalized Willenborg
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Walker-Chang Willenborg
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Constant closure
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Strip yield crack closure model
Materials
Engineering Department
Structural Engineering Department
Mechanical & Materials Engineering
Division
SwRI Home
Southwest Research Institute® (SwRI®) is an independent, nonprofit, applied engineering and physical sciences research and development organization with 11 technical divisions using multidisciplinary approaches to problem solving. The Institute occupies 1,200 acres and provides nearly two million square feet of laboratories, test facilities, workshops, and offices for more than 3,300 employees who perform contract work for industry and government clients.