ISSN: 1546-962X
Page Count: 12

Mechanism-Based Variability in Fatigue Life of Ti-6Al-2Sn-4Zr-6Mo
Jha, SK
Systran Federal Corporation, OH

Larsen, JM
Air Force Research Laboratory, Materials and Manufacturing Directorate, AFRL/MLLMN, Wright Patterson AFB, OH

Rosenberger, AH
The University of Dayton Research Institute, OH

Hartman, GA

Abstract

The variability in fatigue life of a Ti-6Al-2Sn-4Zr-6Mo alloy was studied. The cumulative life distribution plot was found to be composed of two distinct failure mechanisms, designated as Type-I and Type-II. The likelihood of Type-I vs. Type-II failure shifted with respect to the stress level, such that at lower stress levels, there was increased probability of Type-II failure. It also was found that the variability in life was introduced primarily at the crack nucleation stage, specifically, formation of a stage-I crack across an equiaxed primary-α particle.

Keywords:
microstructure, fatigue life variability, crack nucleation, crack growth, probability of failure, deformation, slip transfer

Paper ID: JAI11570
DOI: 10.1520/JAI11570
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