ISSN: 1945-7553
CODEN: JTEVAB
Page Count: 8

Determination of Fracture Toughness J_Ic Under Quasi-Static and Dynamic Loading Conditions Using Wedge Loaded Specimens

Bayoumi, MR
Graduate student and associate professor, University of Manitoba, Winnipeg, Manitoba

Klepaczko, JR
Professor, Institute of Fundamental Technological Research, Polish Academy of Sciences, Warsaw,

Nabil Bassim, M
Graduate student and associate professor, University of Manitoba, Winnipeg, Manitoba

Abstract

A study of the variation of fracture toughness of American Iron and Steel Institute (AISI) 1045 (Unified Numbering System [UNS] G10450) steel in the annealed condition, which exhibits elastic-plastic behavior at the crack tip, with loading rates ranging from quasi-static to dynamic conditions was undertaken. A wedge loaded compact tension (WLCT) specimen geometry was used in both testing conditions. The onset of crack propagation was detected using a strain gage mounted near the crack tip. The fracture parameter J_Ic decreases by about 50% when the loading rate ˙K_I increases from 0.5 to about 10⁶ MPa · m^½ s⁻¹. The measured values of J_Ic using WLCT specimens were confirmed from previous data on this material using standardized three-point bending specimens as well as from evaluation of J_Ic from stretch zone width measurements using scanning electron microscopy of the fracture surface of the WLCT specimens.

Keywords:
dynamic tests, fracture tests, loading rate, J integral, dynamic toughness testing, stretch zone, split Hopkinson bar

Paper ID: JTE10732J
DOI: 10.1520/JTE10732J
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