1.1 This test method covers the determination of fracture propagation toughness in terms of the steady-state crack-tip-opening angle using the drop-weight tear test (DWTT). The method is intended to be used for structural steels exhibiting ductile-dominant fracture (at least 85% shear area measured according to ASTM E436). 1.2 For apparatus, specimen design, and test methodology, this test method draws from ASTM E436: Standard Test Method for Drop-Weight Tear Tests of Ferritic Steels and API 5L3: Recommended Practice for Conducting Drop-Weight Tear Tests on Line Pipe. 1.3 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
The proposed standard test method is to address fast-ductile fracture propagation and arrest in high-pressure pipelines. Traditionally, the Charpy-V notch (CVN) absorbed energy specimen, as per ASTM E-23, has been used for determining the fracture arrest toughness. But shortcomings of the CVN test have become evident when used to characterize modern high-strength and high-toughness steels.
Keywordscrack-tip-opening angle, CTOA; ductile fracture; drop-weight tear test; structural steels; fracture propagation resistance; impact loading
The title and scope are in draft form and are under development within this ASTM Committee.Back to Top