Author(s)

A. Gilat and C.S. Cheng

Abstract

The torsional split Hopkinson bar is used for testing materials at strain rates above 10^ s"^. This strain rate, which is an order of magnitude higher than is typical with this technique, is obtained by using very short specimens. Strain rates of 6.2x10^ s"^ have been achieved with specimens having gage length of 0.1524 mm. Results from tests on 1100 aluminum show an increase in rate sensitivity as the strain rate increases. 1 Introduction Measuring stress-strain curves of materials during deformation at strain rates above about 50 s'Ms difficult. Standard techniques that are used in quasi-static tests cannot be used in high rate tests because of the presence of waves (the deformation in the specimen is not homogeneous) and the effects of inertia. For testing at higher rates, the split Hopkins

Keywords