Head, Structural Mechanics Branch, Naval Research Laboratory, Washington, D.C.,
Pages: 27 Published: Jan 1983
Taken from a recent Naval Research Laboratory (NRL) report, this paper advances author's earlier efforts to associate plastic flow with fatigue crack growth characteristics. Success with this could lessen the data required for estimates of fatigue crack propagation life of structural elements. The model sees crack growth as a means of strain hardening material elements adjacent to the crack tip to counteract strength losses due to transient stress relaxation/creep and environmental surface attack. It defines limiting growth rates in terms of fixed as well as of strain-limited environmental action. Data on some 16 steels are compared to measured stress-strain data using the same model equations. Data fits are rather close, and values of the three kinds of data fitting parameters show consistent trends with respect to the yield strength of the steels.
fatigue crack propagation, corrosion fatigue of steels, fatigue propagation model, plastic flow versus fracture model, fracture mechanics
Paper ID: STP37083S