ASTM B646-97

1.1 This practice provides guidance for testing (a) thin products, of thicknesses equivalent to sheet that is, ([∧lt;=]0.249 in. (6.30 mm)), (b) intermediate thicknesses of plate, forgings, and extrusions, too thin for valid plane-strain fracture toughness testing but too thick for treatment as sheet, that is over 0.249 in. (6.30 mm) and up to 1 to 2 in. (25 to 50 mm), dependent upon toughness level, and (c) relatively thick products where Test Method E399 is applicable. For changes to this specification since the last issue, refer to the Summary of Changes section at the end of the standard.

1.2 This practice addresses the problem of screening tests, recognizing the complexity and expense of making formal fracture toughness measurements on great quantities of production lots, and provides alternatives in the form of simpler, less expensive tests that may be carried out either in a research or production test laboratory.

1.3 The values stated in inch-pound units are to be regarded as the standard.

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.