DYMAT 2009
Volume 1, 2009
DYMAT 2009 - 9th International Conference on the Mechanical and Physical Behaviour of Materials under Dynamic Loading
Page(s) 457 - 462
Section Experimental Techniques
Published online 15 September 2009
DYMAT 2009 (2009) 457-462
DOI: 10.1051/dymat/2009065

An electrical pulse-heated Kolsky bar technique for high strain rate flow stress measurements of rapidly heated metals

S.P. Mates1, S. Banovic1, R. Rhorer1, T. Burns1, E. Whitenton1 and D. Basak2

1  National Institute of Standards and Technology, Gaithersburg, MD, USA
2  Orbital Sciences Corporation, Dulles, VA, USA

Published online: 15 September 2009

We have developed a unique electrical pulse-heated Kolsky Bar technique for measuring the flow stress of metals at heating rates of up to 6000°C per second and strain rates up to 104 per second. Under these conditions, which are approaching those found in high speed machining, thermally activated microstructural processes such as grain growth, solid state phase transformation and dislocation annealing may be bypassed, leading to unusual non-equilibrium superheated states. Flow stresses may thus differ significantly from equilibrium high temperature conditions. This paper briefly describes our pulse-heated Kolsky bar technique and discusses recent results on an AISI 1075 pearlitic steel heated rapidly up to and beyond the austenite formation temperature.

© EDP Sciences 2009