ASTM F288-96 (2025) PDF

Full title and description

ASTM F288-96 (2025) — Standard Specification for Tungsten Wire for Electron Devices and Lamps. This specification defines the required chemical, mechanical and dimensional characteristics, finishes, and test methods for commercially pure and thoriated tungsten wire and certain tungsten rod intended for use in electron tubes, lamp filaments and other electron-device applications.

Abstract

This standard covers three types of drawn tungsten wire (commercially pure nonsag and thoriated grades) and one type of rod for metal-to-glass sealing. It gives composition limits, tensile and ductility requirements, surface‑flaw acceptance, permitted finishes and packing/ordering information, and references the test methods required for dimensional and mechanical verification. The document is short (typically 5 pages) and focuses on the essential properties and inspection tests needed for electron‑device and lamp manufacturing.

General information

• Status: Active specification (designation F288-96 with reapproval history; listed for the 2025 reapproval/publication cycle by ASTM committee listings and commercial distributors).
• Publication date: Current retail listings show an F288-96(2025) edition dated 01 February 2025; historically the document was reapproved as F288-96R14 (2014) and updated on ASTM retail pages (last posted update 2019).
• Publisher: ASTM International (ASTM Committee F01 / Subcommittee F01.03 jurisdiction).
• ICS / categories: Materials / Wires — commonly catalogued under ICS 29.060.10 (wires) and included in Book of Standards volume for Committee F01.
• Edition / version: Designation F288 − 96 with reapproval annotations (commonly referenced as F288-96R14 for the 2014 reapproval and shown in distributor catalogs as F288-96(2025) for the 2025 cycle).
• Number of pages: 5 (typical published length).

Scope

The specification applies to drawn tungsten wire suitable for fabrication into parts for electron tubes, lamps and other electron devices (grid wire excluded) and to one grade of rod for metal‑to‑glass sealing. It defines Type 1A (commercially pure nonsag wire), Type 1B (commercially pure rod for seals), Type 2A (1% thoria filament wire) and Type 2B (2% thoria filament wire), along with the required units, dimensional conventions and ordering information. The scope also references the relevant test methods for diameter, surface flaws, tensile and ductility testing.

Key topics and requirements

• Classification of wire/rod types: Type 1A, Type 1B, Type 2A (1% thoria), Type 2B (2% thoria).
• Chemical composition limits and UNS designations (Types 1A/1B = UNS R07005; Type 2A = UNS R07911; Type 2B = UNS R07912).
• Mechanical requirements: specified tensile strength ranges and ductility acceptance tests (number of allowable breaks or mandrel‑wrap tests depending on mass/diameter).
• Surface‑flaw acceptance criteria and referenced surface‑inspection test method(s).
• Finish and straightness options (multiple finish levels; requirements for clean/bright vs black finishes and for straightened wire for certain applications).
• Dimensional conventions and weight/diameter conversion formulas used for specifying sizes and tolerances.
• Referenced test methods and standards used for verification (examples include ASTM test methods for diameter, surface flaws, tensile and sag tests as cited in the standard).

Typical use and users

Primary users are manufacturers and suppliers of electron‑device components and lamp filaments (vacuum tube and specialty lamp producers), materials engineers, quality and incoming‑inspection personnel, and purchasers specifying filament and seal wire. Research labs, contract manufacturers and metallurgical test houses also use the specification when accepting or testing tungsten wire for electronic and lighting applications.

Related standards

Standards commonly referenced alongside F288 include ASTM test methods and specifications for surface flaws, diameter measurement and sag testing of tungsten wire (for example F204, F205, F269 and other F‑series test methods), related tungsten and molybdenum wire/rod specifications (e.g., F289 for molybdenum wire/rod, F73 for tungsten‑rhenium alloys) and applicable ISO/IEC material test methods as needed. Committee listings and catalogs group these documents under the same subcommittee jurisdiction.

Keywords

tungsten wire, filament wire, thoriated tungsten, nonsag tungsten, UNS R07005, UNS R07911, UNS R07912, electron devices, lamp filament, wire finishes, tensile strength, ductility, surface flaws.

FAQ

Q: What is this standard?

A: ASTM F288-96 is the Standard Specification for Tungsten Wire for Electron Devices and Lamps; it sets composition, mechanical and surface requirements for commercially pure and thoriated tungsten wire and certain rod intended for electron‑device and lamp use.

Q: What does it cover?

A: It covers types/grades of tungsten wire and rod (Types 1A, 1B, 2A, 2B), chemical designations, tensile and ductility requirements, permissible finishes, dimensional/weight conversions and the inspection/test methods required for acceptance.

Q: Who typically uses it?

A: Wire and rod producers, lamp and electron‑device manufacturers, purchasing/specification engineers, QA/QC laboratories, and metallurgical testing services use this standard to ensure material conformity and interchangeability.

Q: Is it current or superseded?

A: The core designation is F288-96 with a documented reapproval history (for example F288-96R14). Commercial catalogs and committee listings show a 2025 reapproval/publication cycle (F288-96(2025)); users should confirm the exact edition/version required when procuring or citing the standard (ASTM International is the definitive source for the current official text).

Q: Is it part of a series?

A: It is part of the ASTM F01 committee portfolio (electronics) and is commonly paired with related F‑series test methods and specifications for tungsten and molybdenum materials used in electron devices and lamps. See subcommittee listings for adjacent standards and related reapproval items.

Q: What are the key keywords?

A: tungsten wire, filament, thoriated tungsten, nonsag, UNS R07005, UNS R07911, electron devices, lamp filament, surface flaws, tensile, ductility.