Dynamic high-temperature Kolsky tension bar techniques

¹ Sandia National Laboratories, Albuquerque, NM 87185, USA
² Sandia National Laboratories, Livermore, CA 94550, USA
³ Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA

^a e-mail: bsong@sandia.gov
^b e-mail: knelso@sandia.gov
^c e-mail: rjlipin@sandia.gov
^d e-mail: jbignel@sandia.gov
^e e-mail: ulrichgb@ornl.gov
^f e-mail: easo.george@rub.de

Published online: 7 September 2015

Abstract

Kolsky tension bar techniques were modified for dynamic high-temperature tensile characterization of thin-sheet alloys. An induction coil heater was used to heat the specimen while a cooling system was applied to keep the bars at room temperature during heating. A preload system was developed to generate a small pretension load in the bar system during heating in order to compensate for the effect of thermal expansion generated in the high-temperature tensile specimen. A laser system was applied to directly measure the displacements at both ends of the tensile specimen in order to calculate the strain in the specimen. A pair of high-sensitivity semiconductor strain gages was used to measure the weak transmitted force due to the low flow stress in the thin specimen at elevated temperatures. As an example, the high-temperature Kolsky tension bar was used to characterize a DOP-26 iridium alloy in high-strain-rate tension at 860 s⁻¹/1030 ^∘C.