Mechanical Aspects of the Dynamic Tear Test

Abstract

The impact forces and specimen bending moments generated during the NRL dynamic tear test are interpreted in terms of the dynamics of the system and the fracture characteristics of the material. It is shown that the impact forces and bending moments up to the time of crack initiation can be predicted using a simple analysis based on Timoshenko’s treatment of transverse beam impact problems. This implies the possibility of using this analysis for dynamic KIc determinations.

Numerical simulation of anvil interactions in the impact testing of notched bend specimens

“…(b) test results for a PMMA specimen.specimen under an indentor obtained using the test set-up shown inFigure 3indicates that a linear relationship provides a good approximation to the actual. This observation is supported by the test data on steel and aluminum published by Nash and Lange[20]. Hence a linear spring can be used to represent the contact deformations at the support point.…”

Effect of First Reflections in Dynamic Tear Test

“…Dynamic brittle fracture studies are often (Timoshenko, 1913;Mason, 1936;Lee, 1940;Eringen, 1953;Nash and Lange, 1969;Zehnder and Rosakis, 1986) based on the dynamic tear (OT), or three-point bend, test. In this test, a mass impacts the unnotched side of a simply-supported, notched rectangular bar, and the resultinq elastic wave diffraction at the notch causes fracture there.…”

Stress Field Variations during Dynamic Loading

“…Impact tests leading to the brittle fracture of A517 steel dynamic tear specimens have been performed and the history of the impact force measured [10].…”