Accession Number : AD0726998


Title :   The Development and Use of a Torsional Split Hopkinson Bar for Experiments in Dynamic Plasticity.


Descriptive Note : Summary technical rept. Sep 69-Dec 70,


Corporate Author : AIR FORCE MATERIALS LAB WRIGHT-PATTERSON AFB OHIO


Personal Author(s) : Nicholas,Theodore ; Campbell,J D E


Report Date : May 1971


Pagination or Media Count : 39


Abstract : The development and use of a torsional split-Hopkinson bar testing apparatus for determining the mechanical properties of materials at high rates of strain is described. The apparatus is capable of generating a smooth torsional pulse with a rise-time of approximately 20 microseconds and can be used to generate shear stress-strain data at strain rates above 1000/sec. Experimental data are presented for an aluminum alloy. Results of incremental wave propagation tests on quasistatically prestressed specimens of an essentially 'rate-independent' metal indicate that the velocity of propagation of the wave front is that of an elastic shear wave which is in agreement with the rate-dependent theory of plastic wave propagation. (Author)


Descriptors :   *TORSION METERS , CONFIGURATIONS , STRESSES , STRAIN(MECHANICS) , MEASUREMENT , STRAIN GAGES , ASSEMBLY , TEST EQUIPMENT , TEST METHODS , ALUMINUM ALLOYS , EXPERIMENTAL DATA


Subject Categories : Test Facilities, Equipment and Methods


Distribution Statement : APPROVED FOR PUBLIC RELEASE