ASTM B646-17
(Practice)Standard Practice for Fracture Toughness Testing of Aluminum Alloys
Standard Practice for Fracture Toughness Testing of Aluminum Alloys
SIGNIFICANCE AND USE
5.1 This practice is provided to develop and maintain uniformity in practices for the evaluation of the toughness of aluminum alloys, particularly with regard to supplier qualification, quality assurance, and material release to specifications.
5.2 It is emphasized that the use of these procedures will not alter the validity of data determined with specific test methods, but provides guidance in the interpretation of test results (valid or invalid) and guidance in the selection of a reasonable test procedure in those instances where no standard exists today.
SCOPE
1.1 Fracture toughness is a key property for a number of aluminum alloys utilized in aerospace and process industries. Fracture toughness testing is often required for supplier qualification, quality control, and material release purposes. The purpose of this practice is to provide uniform test procedures for the industry, pointing out which current standards are utilized in specific cases, and providing guidelines where no standards exist. This practice provides guidance for testing (a) sheet and other products having a specified thickness less than 6.35 mm (0.250 in.), (b) intermediate thicknesses of plate, forgings, and extrusions that are too thin for valid plane-strain fracture toughness testing but too thick for treatment as sheet, such as products having a specified thickness greater than or equal to 6.35 mm (0.250 in.) but less than 25 to 50 mm (1 to 2 in.), depending on toughness level, and (c) relatively thick products where Test Method E399 is applicable.
1.2 This practice addresses both direct measurements of fracture toughness and screening tests, the latter recognizing the complexity and expense of making formal fracture toughness measurements on great quantities of production lots.
1.3 The values stated in SI units are to be regarded as the standard. The values in inch-pound units given in parenthesis are provided for information purposes 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.
1.5 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.
General Information
Relations
Buy Standard
Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: B646 − 17
Standard Practice for
1
Fracture Toughness Testing of Aluminum Alloys
This standard is issued under the fixed designation B646; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope* mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee.
1.1 Fracture toughness is a key property for a number of
aluminum alloys utilized in aerospace and process industries.
2. Referenced Documents
Fracture toughness testing is often required for supplier
2
2.1 ASTM Standards:
qualification, quality control, and material release purposes.
The purpose of this practice is to provide uniform test B557 Test Methods for Tension Testing Wrought and Cast
Aluminum- and Magnesium-Alloy Products
procedures for the industry, pointing out which current stan-
dards are utilized in specific cases, and providing guidelines B557M Test Methods for Tension Testing Wrought and Cast
Aluminum- and Magnesium-Alloy Products (Metric)
where no standards exist. This practice provides guidance for
B645 Practice for Linear-Elastic Plane–Strain Fracture
testing (a) sheet and other products having a specified thick-
Toughness Testing of Aluminum Alloys
nesslessthan6.35mm(0.250in.),(b)intermediatethicknesses
E399 Test Method for Linear-Elastic Plane-Strain Fracture
of plate, forgings, and extrusions that are too thin for valid
Toughness K of Metallic Materials
plane-strain fracture toughness testing but too thick for treat-
Ic
E561 Test Method forK Curve Determination
ment as sheet, such as products having a specified thickness
R
E1304 Test Method for Plane-Strain (Chevron-Notch) Frac-
greater than or equal to 6.35 mm (0.250 in.) but less than 25 to
ture Toughness of Metallic Materials
50 mm (1 to 2 in.), depending on toughness level, and (c)
relatively thick products where Test Method E399 is appli- E1823 TerminologyRelatingtoFatigueandFractureTesting
cable.
3. Terminology
1.2 This practice addresses both direct measurements of
3.1 The terminology and definitions in the referenced
fracture toughness and screening tests, the latter recognizing
documents, especially E1823, are applicable to this practice.
the complexity and expense of making formal fracture tough-
ness measurements on great quantities of production lots.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 For purposes of this practice, the following descrip-
1.3 The values stated in SI units are to be regarded as the
tions of terms are applicable in conjunction with Test Method
standard. The values in inch-pound units given in parenthesis
E561:
are provided for information purposes only.
3.2.2 CMOD—crack mouth opening displacement; the mea-
1.4 This standard does not purport to address all of the
surement of specimen displacement between two points span-
safety concerns, if any, associated with its use. It is the
ning the machined notch at locations specific to the specimen
responsibility of the user of this standard to establish appro-
being tested.
priate safety and health practices and determine the applica-
3.2.3 K —a value of K on the K curve based on a 25 %
R25 R R
bility of regulatory limitations prior to use.
secant intercept of the force-CMOD test record from a C(T)
1.5 This international standard was developed in accor-
specimen and the effective crack size a at that point that
e
dance with internationally recognized principles on standard-
otherwise satisfies the remaining-ligament criterion of Test
ization established in the Decision on Principles for the
Method E561. If the maximum force is reached prior to the
Development of International Standards, Guides and Recom-
25 % secant intercept point, the maximum force point shall be
used instead to determine the K value.
R25
1
This practice is under the jurisdiction of ASTM Committee B07 on Light
Metals and Alloys and is the direct responsibility of Subcommittee B07.05 on
2
Testing. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Current edition approved Aug. 1, 2017. Published August 2017. Originally contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
approved in 1978. Last previous edition approved in 2012 as B646 – 12. DOI: Standards volume information, refer to the standard’s Document Summary page on
10.1520/B0646-17. the ASTM website.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1
--------
...
This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: B646 − 12 B646 − 17
Standard Practice for
1
Fracture Toughness Testing of Aluminum Alloys
This standard is issued under the fixed designation B646; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope*
1.1 Fracture toughness is a key property for a number of aluminum alloys utilized in aerospace and process industries. Fracture
toughness testing is often required for supplier qualification, quality control, and material release purposes. The purpose of this
practice is to provide uniform test procedures for the industry, pointing out which current standards are utilized in specific cases,
and providing guidelines where no standards exist. This practice provides guidance for testing (a) sheet and other products having
a specified thickness less than 6.35 mm (0.250 in.), (b) intermediate thicknesses of plate, forgings, and extrusions that are too thin
for valid plane-strain fracture toughness testing but too thick for treatment as sheet, such as products having a specified thickness
greater than or equal to 6.35 mm (0.250 in.) but less than 25 to 50 mm (1 to 2 in.), depending on toughness level, and (c) relatively
thick products where Test Method E399 is applicable.
1.2 This practice addresses both direct measurements of fracture toughness and screening tests, the latter recognizing the
complexity and expense of making formal fracture toughness measurements on great quantities of production lots.
1.3 The values stated in SI units are to be regarded as the standard. The values in inch-pound units given in parenthesis are
provided for information purposes 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.
1.5 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.
2. Referenced Documents
2
2.1 ASTM Standards:
B557 Test Methods for Tension Testing Wrought and Cast Aluminum- and Magnesium-Alloy Products
B557M Test Methods for Tension Testing Wrought and Cast Aluminum- and Magnesium-Alloy Products (Metric)
B645 Practice for Linear-Elastic Plane–Strain Fracture Toughness Testing of Aluminum Alloys
E399 Test Method for Linear-Elastic Plane-Strain Fracture Toughness K of Metallic Materials
Ic
E561 Test Method forK Curve Determination
R
E1304 Test Method for Plane-Strain (Chevron-Notch) Fracture Toughness of Metallic Materials
E1823 Terminology Relating to Fatigue and Fracture Testing
3. Terminology
3.1 The terminology and definitions in the referenced documents, especially E1823, are applicable to this practice.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 For purposes of this practice, the following descriptions of terms are applicable in conjunction with Test Method E561:
3.2.2 CMOD—crack mouth opening displacement; the measurement of specimen displacement between two points spanning the
machined notch at locations specific to the specimen being tested.
1
This practice is under the jurisdiction of ASTM Committee B07 on Light Metals and Alloys and is the direct responsibility of Subcommittee B07.05 on Testing.
Current edition approved May 1, 2012Aug. 1, 2017. Published June 2012August 2017. Originally approved in 1978. Last previous edition approved in 20062012 as
B646 – 06a.B646 – 12. DOI: 10.1520/B0646-12.10.1520/B0646-17.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1
---------------------- Page: 1 ----------------------
B646 − 17
3.2.3 K —a value of
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.