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.

1.3 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are for information only.