Accession Number:

ADA109296

Title:

Surface Reactions and Fatigue Crack Growth

Descriptive Note:

Technical rept.

Corporate Author:

LEHIGH UNIV BETHLEHEM PA INST OF FRACTURE AND SOLID MECHANICS

Personal Author(s):

Report Date:

1981-08-01

Pagination or Media Count:

20.0

Abstract:

Recent fracture mechanics and surface chemistry studies of environment assisted crack growth in gaseous environments have shown that crack growth may be controlled in some systems by the rate of surface reactions and in others by the rate of transport of the aggressive environment to the crack tip. Based on considerations of surface reactions and gas transport, a model for surface reaction and transport controlled fatigue crack growth in single component gaseous environments was proposed and experimentally verified. In practice, however, there is usually more than one gas in a given environment. The various component gases can compete for surface reaction sites and therefore alter the fatigue crack growth response. In this paper, the development of the model for surface reaction and transport controlled fatigue crack growth in single component gaseous environments is briefly reviewed. Modeling of fatigue crack growth in a binary gas mixture, in which one of the components acts as an inhibitor, is described, and the model is applied to the consideration of the influence of oxygen on fatigue crack growth in humid air. Author

Subject Categories:

  • Properties of Metals and Alloys
  • Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE