The crack-tip opening angle (CTOA) as a controlling fracture parameter to predict fast ductile fracture propagation and arrest has been proposed for gas pipeline design and materials selection. However, a simple test, preferably practical in mill test environments, is lacking to characterize CTOA of pipe steels. Drop-weight tear test (DWTT) specimens are used by pipe mills and have been proposed for CTOA characterization but a reliable method to obtain CTOA from such specimens is still under development. Recently, a simplified single-specimen CTOA method (S-SSM) for DWTT specimens has been proposed and may be suitable for a mill test. This paper presents the details of experimental validation of the S-SSM using six commercial pipe steels under quasi-static (5×10~(-5) m/s) and impact (5.1 m/s) loading rates. Remaining questions for further research are discussed.
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