ASTM B770-21 PDF

ABSTRACT This specification establishes requirements for copper-beryllium alloy sand castings for general applications and covers Copper Alloy UNS Nos. C81400, C82000, C82200, C82400, C82500, C82510, C82600, C82800, and C96700. The product shall be manufactured by casting and thermal treatment. Castings shall conform to the chemical composition requirements prescribed for copper, nickel, silicon, beryllium, cobalt, chromium, iron, zirconium, tin, and manganese. The standard temper designations include TF00 (cast, solution and precipitation heat treated) and M01 (as sand cast). Requirements for precipitation and solution heat-treatments of castings for the purpose of determining conformance to the specified mechanical properties including tensile strength, yield strength, and elongation are detailed. Special combinations of properties such as increased ductility, electrical conductivity, dimensional accuracy, and endurance life may be obtained by special precipitation heat-treatments. Tension tests shall also meet the mechanical property requirements. SCOPE 1.1 This specification establishes requirements for sand castings produced from copper-beryllium alloys. The following alloys are covered: Copper Alloy UNS No. Designation Copper Nickel Beryllium C81400 70C 99.1 ... 0.06 C82000 10C 97 ... 0.5 C82200 3C, 14C 98 2.0 0.5 C82400A 165C, 165CTA 97.8 ... 1.7 C82500A 20C, 20CTA 97.2 ... 2.0 C82510 21C 96.6 ... 2.0 C82600A 245C, 245CTA 96.8 ... 2.4 C82800A 275C, 275CTA 96.6 ... 2.6 C96700 72C 67.2 31.0 1.2 1.2 Units—The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 1.3 The following safety hazard caveat pertains only to the test methods described in this specification: 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, health, and environmental practices and determine the applicability of regulatory requirements prior to use. 1.4 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.