A Kolsky bar: Tension,tension-tension

The present paper introduces a new technique which combines rotation disk and traditional Kolsky bar (often termed as split-Hopkinson bar). This technique can be employed to study the tension stress-strain relations and tension-unloading-tension strain-rate history effects of materials in the strain rate range from 10²–10³s⁻¹. The rise time of the incident wave is as short as 15 μs because of the particular design. An attempt is made to estimate strain error caused by the thread connection between the specimen and the bars, and stress error due to the mismatch of the cross section of the specimen and bars. A short rise-time incident wave appears to be most advantageous in view of maintaining the accuracy of the stress-strain curve obtained near the initiation. Preliminary tests are performed on the instrument. Comments are made for this design configuration. M. Li (Student Member of SEM), presently at the Department of Aerospace Engineering, Mechanics and Engineering Science, University of Florida, Gainesville, FL 32611, was Research Associate; R. Wang (formerly A.J. Wang) is Professor; and M.-B. Han is Associate Professor, Department of Mechanics, Peking University, Beijing 100871, P.R. China.