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An Empirical Model for Environmental Damage at the Crack Tip

Published online by Cambridge University Press:  21 February 2011

K. -M. Chang
K. -M. Chang*
Affiliation:
General Electric Company, Corporate Research and Development, P.O. Box 8, Schenectady, NY 12301
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Abstract

An experimental method that is able to verify and to characterize the damage zone developed in front of crack tip under time-dependent fatigue crack propagation has been established. The crack growth rate was found to decrease exponentially in the damaged zone. Such a crack growth behavior can be described by a mathematical model which only requires three parameters: initial crack growth rate, (da/dN)q; normal crack growth rate (da/dN)o; and damaged zone size, D. An analyticat relationship has been developed to correlate the temperature and the time of sustained loading to the size of the induced damaged zone.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 125: Symposium N – Materials Stability and Environmental Degradation , 1988 , 243
Copyright
Copyright © Materials Research Society 1988

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References

REFERENCES

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