Author(s)

J. K. Na, J. Frouin & S. Sathish

Abstract

Nondestructive fatigue damage assessment for Ti-6Al-4V alloy J. K. ~ a ' , J. ~ r o u i n ~ & S. sathish2 ' Veridian Engineering, USA 'University of Dayton Research Institute, USA Abstract Titanium alloys are widely used for aircraft structures, especially Ti-6A1-4V alloy for jet engine parts. In this work, a nondestructive method that can be used to assess fatigue damage in metals is presented. Several experimental results are shown and an attempt is made to correlate the level of fatigue damage with the acoustic nonlinearity parameter, P. The difference between Low Cycle Fatigue (LCF) and ,High Cycle Fatigue (HCF) damage is discussed in terms of P and microstructure dislocation density. For LCF, the damage is found to be wide spread over a big area, while a localized damage pattern for HCF in a relatively small area. The dislocation density data taken with a TEM also shows a good correlation with p. 1 Introduction Under a cyclic mechanical loading, metals undergo fatigue damage inducing cha

Keywords