Annual Performance Report for Grant N00014-93-1-1049 (University of Missouri)
Abstract
The first goal of this project is to determine the effects of plastically induced microstresses on fatigue crack propagation in steel. To accomplish this specimens and heat treatment have been designed, the specimens have been deformed to introduce different microstress states, and the microstresses measured using neutron diffraction. Neutron measurements of the stresses in the cementite phase were successful and confirm that only microstresses are produced by the plastic deformation. Initial results from the neutron measurements of the microstresses indicate that there is some asymmetry in the magnitude of the stresses introduced by tensile and compressive deformations. This effect is probably due to preexisting thermal residual microstresses between the phases. Fatigue crack propagation tests are now being performed. Residual microstresses, Neutron diffraction, Fatigue.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 19, 1994
- Accession Number
- ADA283872
Entities
People
- R. A. Winholtz
Organizations
- University of Missouri