1.1本规范涵盖通过真空电弧熔炼、电子束熔炼或粉末冶金固结制备的非合金和合金钽锭，以生产用于加工各种轧机形状的固结金属。 1.2本规范涵盖的材料包括: 1.2.1 R05200，非合金钽，电子束炉或真空电弧熔炼，或两者， 1.2.2 R05400，非合金钽，粉末冶金固结， 1.2.3 R05255，钽合金，90%钽10%钨，电子束炉或真空电弧熔炼，或两者， 1.2.4 R05252，钽合金，97.5%钽2.5%钨，电子束炉或真空电弧熔炼，或两者，以及， 1.2.5 R05240钽合金、60%钽、40%铌、电子束炉或真空电弧熔炼，或两者兼有。 ====意义和用途====== 为了确定是否符合表中所列特性要求的规定限值，应按照实施规程E 29的舍入方法对观察值或计算值进行舍入 .

1.1 This specification covers unalloyed and alloyed tantalum ingots prepared by vacuum-arc melting, electron-beam melting, or powder-metallurgy consolidation to produce consolidated metal for processing to various mill shapes. 1.2 The materials covered by this specification are: 1.2.1 R05200, unalloyed tantalum, electron-beam furnace or vacuum-arc melt, or both, 1.2.2 R05400, unalloyed tantalum, powder-metallurgy consolidation, 1.2.3 R05255, tantalum alloy, 90 % tantalum 10 % tungsten, electron-beam furnace or vacuum-arc melt, or both, 1.2.4 R05252, tantalum alloy, 97.5 % tantalum 2.5 % tungsten, electron-beam furnace or vacuum-arc melt, or both, and, 1.2.5 R05240 tantalum alloy, 60 % tantalum 40 % columbium, electron-beam furnace or vacuum-arc melt, or both. ====== Significance And Use ====== For the purpose of determining compliance with the specified limit for requirements of the properties listed in the tables, an observed value or a calculated value shall be rounded as indicated in accordance with the rounding method of Practice E 29 .