ASTM B521-25 PDF

Full title and description

ASTM B521-25 — Standard Specification for Tantalum and Tantalum Alloy Seamless and Welded Tubes. Specifies chemical, mechanical and dimensional requirements, permitted grades (UNS R05400, R05200, R05252, R05255, R05240), manufacturing methods for seamless and welded tubes, and required tests and inspection methods for acceptance.

Abstract

This specification covers seamless and welded tubes made from tantalum and selected tantalum alloys intended for corrosion-resistant and specialty applications. It defines allowable grades, manufacturing routes (seamless and fusion-welded without filler metal), dimensional tolerances, mechanical-property tests (tensile, flaring, reverse flattening), and nondestructive examination (hydrostatic, pneumatic, helium-leak, ultrasonic) and inspection requirements. Inch‑pound units are the standard; SI conversions are informational only.

General information

• Status: Active
• Publication date: April 10, 2025 (current 2025 edition)
• Publisher: ASTM International
• ICS / categories: 77.150.99 — Other products of non‑ferrous metals
• Edition / version: ASTM B521-25 (2025)
• Number of pages: 5

Scope

Specifies requirements for tantalum and tantalum‑alloy tubes in both seamless and welded forms for the following UNS grades: R05400 (unalloyed, powder‑metallurgy), R05200 (unalloyed, vacuum melted), R05252 (Ta + 2.5% W), R05255 (Ta + 10% W), and R05240 (Ta‑Nb 60/40). Covers permitted production methods, required mechanical tests (tensile, flaring, reverse flattening), nondestructive examinations (hydrostatic, pneumatic, helium leak, ultrasonic), dimensional and finish requirements, and the use of inch‑pound units as normative.

Key topics and requirements

• Designated UNS grades and their alloy compositions (R05400, R05200, R05252, R05255, R05240).
• Manufacturing methods: seamless production methods and fusion welded tube from flat‑rolled stock without filler metal.
• Mechanical testing: tensile properties, yield, elongation, flaring and reverse‑flattening tests for tube integrity.
• Nondestructive testing and inspection: hydrostatic, pneumatic, helium‑leak and ultrasonic tests as applicable.
• Dimensional tolerances, wall thickness and OD ranges, and surface/finish requirements for acceptance.
• Use of inch‑pound units as the standard; SI conversions provided for information only.
• Rounding and reporting of test values per referenced practices (e.g., ASTM practice on rounding methods).

Typical use and users

Used by tube manufacturers, material suppliers, purchasing/specification engineers, quality and inspection personnel, and end users in chemical processing, corrosive service systems, electronics, aerospace, medical device components, and other specialty applications where tantalum’s corrosion resistance and alloy properties are required.

Related standards

Previous and related documents include earlier editions of ASTM B521 (for example B521‑22, B521‑19), and other ASTM standards and practices referenced for testing and reporting (such as rounding/reporting practices and relevant nondestructive test methods). Related material standards for tantalum or specialty metal tubing and complementary product specifications may also apply depending on the application.

Keywords

tantalum, tantalum alloy, seamless tube, welded tube, UNS R05400, UNS R05200, UNS R05252, UNS R05255, UNS R05240, nondestructive test, hydrostatic test, helium leak test, tensile test, flaring test, reverse flattening

FAQ

Q: What is this standard?

A: ASTM B521-25 is the 2025 edition of the ASTM specification that defines requirements for tantalum and tantalum‑alloy seamless and welded tubes.

Q: What does it cover?

A: It covers designated UNS tantalum grades, permitted tube manufacturing methods (seamless and fusion welded without filler), dimensional and finish requirements, mechanical-property testing, and nondestructive examinations for acceptance.

Q: Who typically uses it?

A: Tube manufacturers, material and procurement engineers, quality/inspection teams, and end users in chemical processing, electronics, aerospace, medical, and other industries needing corrosion‑resistant tantalum tubing.

Q: Is it current or superseded?

A: It is current and active as of the 2025 edition (ASTM B521‑25). This edition supersedes earlier versions of the specification.

Q: Is it part of a series?

A: Yes. It is developed under ASTM’s metallurgy/metal products committee activities (Book of Standards volume covering B-section metals) and has prior editions (for example the 2022 and 2019 versions). It also references other ASTM practices and test methods used in conjunction with tube acceptance.

Q: What are the key keywords?

A: Tantalum, tantalum alloy, seamless tube, welded tube, UNS R05400, R05200, R05252, R05255, R05240, nondestructive testing, tensile test, hydrostatic test.