ASTM B 820 : 2023

1.1This test method covers the technique of bend testing copper and copper alloy strip samples to determine product formability or the ability to resist cracking when forming a bend around a specific radius. The criterion for failure is the occurrence of cracks on the convex surface of the bend.

1.2This bend test is limited to strip from 0.003 in. to and including 0.031 in. (0.076 mm to and including 0.79 mm) thick.

1.3The forming or punch radius for the bend test shall be determined by agreement between the manufacturer or supplier and purchaser. This punch radius is typically equal to or greater than the minimum bend radius without failure for the alloy, temper and thickness combination of the strip being tested.

1.4Units—The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units which are provided for information only and are not considered standard.

1.5This 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.

1.6This 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.