1.1This specification covers tantalum and tantalum alloy seamless and welded tubes of the following grades:

1.1.1UNS Grade R05400-Unalloyed tantalum, powder-metallurgy consolidation,

1.1.2UNS Grade R05200-Unalloyed tantalum, vacuum melted,

1.1.3UNS Grade R05252-Tantalum + 2.5 % tungsten alloy, vacuum melted.

1.1.4UNS Grade R05255-Tantalum + 10 % tungsten alloy, vacuum melted.

1.1.5UNS Grade R05240-Tantalum alloy, 60 % tantalum, 40 % niobium, electron-beam furnace or vacuum arc melt, or both.

1.2The 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.

1.3This 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.