ASTM E561-22
Standard Test Method for KR Curve Determination

Standard No.

ASTM E561-22

Release Date

2022

Published By

American Society for Testing and Materials (ASTM)

Status

Be replaced

Replace By

ASTM E561-23

Latest

ASTM E561-23

Scope

1.1 This test method covers the determination of the resistance to fracture of metallic materials under Mode I loading at static rates using either of the following notched and precracked specimens: the middle-cracked tension M(T) specimen or the compact tension C(T) specimen. A KR curve is a continuous record of toughness development (resistance to crack extension) in terms of KR plotted against crack extension in the specimen as a crack is driven under an increasing stress intensity factor, K. (1)2 1.2 Materials that can be tested for KR curve development are not limited by strength, thickness, or toughness, so long as specimens are of sufficient size to remain predominantly elastic to the effective crack extension value of interest. 1.3 Specimens of standard proportions are required, but size is variable, to be adjusted for yield strength and toughness of the materials. 1.4 Only two of the many possible specimen types that could be used to develop KR curves are covered in this method. 1.5 The test is applicable to conditions where a material exhibits slow, stable crack extension under increasing crack driving force, which may exist in relatively tough materials under plane stress crack tip conditions. 1.6 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard. 1.7 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

ASTM E561-22 Referenced Document

• ASTM E111 Standard Test Method for Young''s Modulus, Tangent Modulus, and Chord Modulus
• ASTM E1823 Standard Terminology Relating to Fatigue and Fracture Testing
• ASTM E3076 Standard Practice for Determination of the Slope in the Linear Region of a Test Record
• ASTM E399 Standard Test Method for Plane-Strain Fracture Toughness of Metallic Materials
• ASTM E4 Standard Practices for Force Verification of Testing Machines

ASTM E561-22 history

• 2023 ASTM E561-23 Standard Test Method for KR Curve Determination
• 2022 ASTM E561-22 Standard Test Method for KR Curve Determination
• 2021 ASTM E561-21 Standard Test Method for KR Curve Determination
• 2020 ASTM E561-20 Standard Test Method for KR Curve Determination
• 2019 ASTM E561-19e1 Standard Test Method for KR Curve Determination
• 2019 ASTM E561-19 Standard Test Method for KR Curve Determination
• 2015 ASTM E561-15a Standard Test Method for KR Curve Determination
• 2015 ASTM E561-15 Standard Test Method for KR Curve Determination
• 2010 ASTM E561-10e2 Standard Test Method for K-R Curve Determination
• 2010 ASTM E561-10e1 Standard Test Method for K-R Curve Determination
• 2010 ASTM E561-10 Standard Test Method forK-R Curve Determination
• 2008 ASTM E561-08e1 Standard Test Method forK-R Curve Determination
• 2008 ASTM E561-08 Standard Test Method forK-R Curve Determination
• 2005 ASTM E561-05e1 Standard Test Method forK-R Curve Determination
• 2005 ASTM E561-05 Standard Test Method for K-R Curve Determination
• 1998 ASTM E561-98 Standard Practice for R-Curve Determination