Tension and compression tests of two polymers under quasistatic and dynamic loading

Testing methods have been developed to determine the dynamic stress-strain responses and failure behavior of an epoxy, Epon 828/T-403, and a poly(methyl methacrylate) (PMMA) under high-strain-rate uniaxial tension and compression conditions. A split Hopkinson tension bar was modified for the dynamic tensile stress-strain behavior of the low-strength and low-mechanical-impedance specimens. An aluminum split Hopkinson pressure bar was used to determine the dynamic compressive responses. A pulse-shaping technique was employed in both dynamic tension and compression experiments to ensure that valid experimental conditions were satisfied. Results show that, compared with quasi-static behavior, dynamic tension causes smaller failure strains, whereas dynamic compression results in significantly higher compressive strengths for both materials. (C) 2001 Elsevier Science Ltd. All rights reserved.