1.1 This practice covers the determination of the fracture toughness ( K-EE ) of a steel by testing fatigue-cracked bend or compact specimens and interpreting the load displacement curves according to equivalent energy methodology.

1.2 The practice is limited to the analyses of test results from the standard bend and compact specimens of Test Method E399, with exception noted in 7.2 (see Figs. 1 and 2). Size may be a variable.

1.3 Values stated in inch-pound units are to be regarded as the standard. SI units are provided for information only.

1.4 This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety problems 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 .