Accession Number : ADA113486

Title :   On Microstructural Control of Near-Threshold Fatigue Crack Growth in 7000-Series Aluminum Alloys.

Descriptive Note : Final rept.,

Corporate Author : NAVAL RESEARCH LAB WASHINGTON DC

Personal Author(s) : Yoder,G R ; Cooley,L A ; Crooker,T W

PDF Url : ADA113486

Report Date : 02 Apr 1982

Pagination or Media Count : 12

Abstract : Fatigue crack growth rate data for 7000-series aluminum alloys can be approximated with a multilinear form, when plotted in conventional logarithmic coordinates over a sufficiently broad spectrum of delta K. Each transition point in the growth-rate curve appears to be associated with a specific microstructural feature that can serve as a barrier to slip-band transmission, in accord with the cyclic plastic zone model of fatigue crack growth. Evidence strongly suggests that transition to the threshold for fatigue crack growth is controlled by dispersoid particles. (Author)

Descriptors :   *Aluminum alloys, *Crack propagation, *Microstructure, *Fatigue(Mechanics), Control, Threshold effects, Spectra, Transitions, Plastic properties, Rates, Cyclic tests, Dispersing, Particles

Subject Categories : Properties of Metals and Alloys
      Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE