Plasticity of Micrometer-Scale Single-Crystals in Compression: A Critical Review (PREPRINT)
Abstract
This review examines the recent literature that has focused on uniaxial compression experiments of single crystals at the micrometer-scale. Collectively, the studies discovered new regimes of plastic flow that are size-scale dependent and that occur in the absence of strong strain gradients. However, the quantitative comparison of the flow curves between independent studies is hampered by differences in the particular implementations of the testing methodology. Two schools of thought have emerged regarding the observed size-scale effects; one attributes the effects to lack of dislocations in small samples, while the other attributes them to dislocation behavior in truncated volumes. The former, by its nature, lacks quantitative models. The latter has relied on modeling of the microcompression experiment using 3D discrete dislocation simulations, which has provided leading insight into the mechanisms that may control plastic flow in FCC metals. These efforts identified the importance of the initial dislocation density and distribution of mobile segments, as well as altered multiplication and hardening responses due to finite source statistics.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 2008
- Accession Number
- ADA490159
Entities
People
- Dennis M. Dimiduk
- Michael D. Uchic
- Paul A. Shade
Organizations
- Air Force Research Laboratory