A METALLURGICAL STUDY OF HIGH STRAIN RATE DEFORMATION.
Abstract
A systematic study was carried out on the failure of metals subjected to explosive loading. A longitudinal shock wave is passed through a cylindrical specimen which is press fit into a specimen holder of like material. The compressive wave is reflected from the free surface and the specimen is subjected to a tensile load which causes it to fail. It is interesting to note that at pressures several times the static strength of the material, the failure mode is similar to that obtained during static loading, i.e., a necking-down of the specimen and a resultant cup-cone type fracture. Investigations have been carried out for the following materials: high purity copper, 1100 F aluminum, Armco iron, 1020, 1045, 4140 steels, and 304 stainless steel. Single crystals and polycrystalline specimen have been compared for copper. The experimental and analytical results reported are: (1) fracture times as a function of pressure; (2) shear wave velocities generated in the specimen; (3) dynamic theoretical strengths of metals; (4) the effect of size (diameter) of the specimen on its dynamic strength; (5) the influence of internal boundaries on the formation of shear waves. Theoretical treatment of the data shown that the results obtained may be explained by extending Truesdale's analysis on the propagation of an elastic wave in a pre-compressed media, and the use of the BakerEricson inequality for waves at a boundary. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1966
- Accession Number
- AD0629921
Entities
People
- Coy M. Glass
- Gerald L. Moss
- John J. Misey
- Stanley K. Golaski
Organizations
- Ballistic Research Laboratory