ASTM-B646 Standard Practice for Fracture Toughness Testing of Aluminum Alloys

Show Complete Document History

Document Center Inc. is an authorized dealer of ASTM standards.
The following bibliographic material is provided to assist you with your purchasing decision:

Standard Practice for Fracture Toughness Testing of Aluminum Alloys



Changes from the previous issue

A redline edition is available for this document, with all changes visible. Ask Document Center Inc. for more information.


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.

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.


aluminum alloys; fracture toughness; linear-elastic; plane-strain; plane stress; quality assurance;; ICS Number Code 77.120.10 (Aluminium and aluminium alloys)

To find similar documents by ASTM Volume:

02.02 (Aluminum and Magnesium Alloys)

To find similar documents by classification:

77.120.10 (Aluminium and aluminium alloys)

This document comes with our free Notification Service, good for the life of the document.

This document is available in either Paper or PDF format.

Document Number


Revision Level




Modification Type


Publication Date

Aug. 1, 2017

Document Type


Page Count

5 pages

Committee Number