Inelastic Deformation of Metals Under Dynamic Loading.
Abstract
Torsional split-Hopkinson bar experiments, involving jumps in strain rate from 0.0001/s to 1000/s have been carried out on four metals (1100-0 aluminum, OFHC copper, zinc, AZ30B magnesium) at temperatures ranging from -200C to 250C. In addition, the effect of annealing temperature on the strain rate sensitivity of the flow stress has been examined for OFHC copper and a tellurium-doped copper alloy, Amtel. Effects of strain rate and strain rate history observed in these experiments have been examined within the framework of a theory of thermally activated motion, multiplication and annihilation of dislocations. Wavefront and Late-time asymptotic solutions have been obtained for wave propagation in linear elastic and visco-elastic bilaminates. Plastic waves of combined stress have been analyzed using a self-consistent slip model to characterize the stress-strain behavior of polycrystalline aluminum. Solutions have been obtained for three hardening models in which slip on one slip system increases the yield stress on (1) that system only, (2) all systems equally, (3) to a greater degree on nonco-planar systems. Comparison of theory with experiment shows better agreement than when smooth yield surface constitutive models are used. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 03, 1976
- Accession Number
- ADA031083
Entities
People
- J. Duffy
- R. J. Clifton
Organizations
- Brown University