Microstructure plays a key role in fatigue crack initiation and growth. Consequently,
measurements of strain at the microstructural level are crucial to understanding fatigue crack
behavior. The few studies that provide such measurements have relatively limited resolution
or areas of observation. This paper provides quantitative, full-field measurements of plastic
strain near a growing fatigue crack in Hastelloy X, a nickel-based superalloy.
Unprecedented spatial resolution for the area covered was obtained through a novel …