Accession Number:

AD0780733

Title:

Measurement of Strain Rate Effects in Metals.

Descriptive Note:

Final rept.,

Corporate Author:

LEHIGH UNIV BETHLEHEM PA

Personal Author(s):

• Smith,Wesley R.

Report Date:

1974-04-01

Pagination or Media Count:

38.0

Abstract:

A new shock tube technique has demonstrated the existence of strain rate effects in the plastic deformation of metals. A transient deformation is produced in a thin-walled cylindrical metal tube loaded by a plane air shock wave propagating inside it. Surface strain gauges allow a direct measurement of the shock-produced transient strain. Preliminary experiments with annealed aluminum tubes have demonstrated the existence of strain relaxation when the shock-applied normal surface stress exceeds the static elastic limit. Strain relaxation data from these experiments was used with the quasi-static model developed to describe the deformation of the tube. The experimental and model strain-time profiles compared favorably. Modified author abstract

Descriptors:

• *Strain rate
• *Impact tests
• Shock tubes
• Wave propagation
• Plastic deformation
• Aluminum
• Strain gages
• Mathematical models
• Measurement

Subject Categories:

• Metallurgy and Metallography
• Test Facilities, Equipment and Methods

Distribution Statement:

APPROVED FOR PUBLIC RELEASE