【国外标准】 Standard Specification for Commercial Bronze Strip for Bullet Jackets

17.1 For purposes of determining compliance with the specified property limits for the properties listed in the following table, an observed value of a calculated value shall be rounded as indicated in accordance with the rounding method of Practice E29:Property Rounded Unit for Observed orCalculated Value   Chemical compositionHardness nearest unit in the last right-handsignificant digit used in expressingthe limiting value.Tensile strength  nearest ksi (5 MPa)Grain size:   Up to 0.055 mm, incl  nearest multiple of 0.005 mm Over 0.055 to 0.160 mm, incl  nearest 0.01 mmElongation:   5 % and over  nearest 1 %AbstractThis specification covers the standard for commercial bronze strip for manufacture of bullet jacket cups and ammunition components from copper alloy UNS No. C22000. The specimens shall be manufactured by such hot working, cold working, and annealing processes to produce a uniform wrought structure. Each specimen shall be subjected to tension test and Rockwell hardness test. In addition to tensile properties for strips, purchaser may also specify grain size. If specimens fail to conform to the prescribed specification, analysis shall be made on a new composite sample.1.1 This specification establishes the requirements for commercial bronze strip for manufacture of bullet jacket cups and ammunition components from Copper Alloy UNS No. C22000.21.2 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 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.