12.1 The following applies to all specified limits in this standard for purposes of determining conformance with this specification. The observed value or a calculated value shall be rounded off to the nearest unit in the last right-hand digit used in expressing the specification limit, in accordance with the rounding-off method of Practice E29.

This specification covers hafnium alloyed niobium bar, rod, and wire. The material covered by this specification is R04295, a niobium-base alloy containing hafnium and titanium. The alloy shall conform to the required chemical composition for carbon, oxygen, nitrogen, hydrogen, hafnium, titanium, zirconium, tungsten, tantalum, and niobium. Materials in the annealed condition supplied under this specification shall conform to the required mechanical properties such as tensile strength, yield strength, and elongation. The alloy shall undergo the following test methods: room temperature tension test; elevated temperature tension test; and chemical test.

1.1 This specification covers hafnium alloyed niobium bar and wire.

1.2 The material covered by this specification is R04295, niobium-base alloy containing approximately 10 % hafnium and 1 % titanium.

1.3 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.

1.4 The following safety hazards caveat pertains only to the test methods portion, Section 14, of 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 limitations prior to use.

1.5 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.