Accession Number : AD0680247

Title :   DYNAMIC TESTING AND WAVE PROPAGATION IN A STRAIN RATE SENSITIVE MATERIAL,

Corporate Author : SOUTHERN METHODIST UNIV DALLAS TEX DEPT OF STATISTICS

Personal Author(s) : Watson,Hal , Jr

Report Date : 16 DEC 1968

Pagination or Media Count : 30

Abstract : Short specimens of Armco iron were tested at room temperature under compressive, axial loads at strains up to 0.6 percent and strain rates up to 1000 in/in-sec. During loading, the axial stress was measured with a thin, piezoceramic disk inserted between the specimen and loading bar. The surface strain was measured with conventional epoxy-backed, foil strain gages, and the strain rate deduced by differentiating the strain vs. time record. The stress, strain, and strain rate data were plotted and were found to be approximated by a particular constitutive functional. The constitutive equation was then used along with the governing equations of motion and continuity in finding a numerical solution to the problem of a one-dimensional plastic wave propagating in a rate sensitive bar caused by an initial axial stress sigma (0,t). The solutions at two locations for both stress and strain were found to compare favorably with the stress and strain measured in a long bar impact test. (Author)

Descriptors :   (*IRON, MECHANICAL WAVES), (*MECHANICAL WAVES, PROPAGATION), STRAIN(MECHANICS), STRESSES, LOADS(FORCES), SURFACE PROPERTIES, STRAIN GAGES, BOUNDARY VALUE PROBLEMS, NUMERICAL ANALYSIS, COMPUTER PROGRAMMING, COPPER, ALUMINUM

Subject Categories : Metallurgy and Metallography
      Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE