ATTENUATION OF SHOCK WAVES IN SOLIDS
Abstract
Attenuation of shock waves was studied in annealed 1060 aluminum, 2024-T351 aluminum, and Teflon by impacting samples with explosively driven aluminum plates. Free-surface velocities were measured as a function of target thickness by recording the time of flight across a known distance of a thin shim which was originally in intimate contact with the surface of the sample. A streak camera was used as the recording instrument, Experimental results are believed to be more accurate than any obtained previously. Samples of 2024-T351 aluminum were shocked to approximately 110 kbars and 340 kbars by flyer plates having velocities of about 0.125 cm/microsecond 0.33 cm/microsec. respectively. 1060 Aluminum was shocked to 110 kbars and significant difference in its behavior were observed in comparison to the 2024-T351 aluminum. Two models are discussed for representing elastoplastic stress-strain relations. One of these models permits the yield stress to be an arbitrary function of the hydrostatic pressure. The other permits both the shear modulus and the yield stress to vary arbitrarily with the strain. Results of calculations using an artificial viscosity code are given for the two models. The experimental data do not show a stepwise decrease of the free-surface velocity as predicted by the simple elastic-plastic models with a von Mises or Coulomb yield criterion. This qualitative difference is attributed to Bauschinger effect. Results for Teflon indicate that the fluid model may be satisfactory although the data are meager and contain some inconsistencies.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1966
- Accession Number
- AD0482942
Entities
People
- Andrew B. Christensen
- G. R. Fowles
- John O. Erkman
Organizations
- SRI International