ASTM B888/B888M-25 PDF

Full title and description

Standard Specification for Copper Alloy Strip for Use in Manufacture of Electrical Connectors or Spring Contacts — ASTM B888/B888M‑25. This specification establishes composition, mechanical property, temper, dimensional tolerance, and finishing requirements for copper alloy strip intended for electrical connector and spring‑contact manufacture, and references a long list of accepted UNS copper alloy numbers for which the specification applies.

Abstract

This specification covers copper alloy strip produced from specified UNS copper‑alloy numbers for use in electrical connectors and spring contacts. It sets requirements for material form (cast bar, slab, billet, etc.), allowable tempers (annealed, rolled, mill‑hardened), required mechanical properties (tensile strength, yield strength, elongation), dimensional tolerances (thickness, width, straightness, mass), and allowable finishing/heat treatment processes. Units in either SI or inch‑pound are permitted; each system is to be used independently. The specification also notes applicable safety caveats for the test methods described.

General information

• Status: Active (current edition).
• Publication date: April 1, 2025.
• Publisher: ASTM International.
• ICS / categories: 77.150.30 (Products of non‑ferrous metals — Copper products); related classification 77.120.30 (Copper and copper alloys).
• Edition / version: B888/B888M‑25 (designation year 2025).
• Number of pages: 11 pages.

Scope

Specifies requirements for copper alloy strip intended specifically for manufacture of electrical connectors and spring contacts produced from a defined list of UNS copper‑alloy numbers. Covers acceptable starting forms (cast bar, slab, cake, billet, or equivalent), permitted processing routes (hot and cold working, annealing, heat treatment), available tempers, required mechanical property limits (tensile, yield, elongation), dimensional tolerances (thickness, width, length, straightness, mass), and unit systems (SI or inch‑pound, used independently). The standard also directs users to related specifications for alloys not covered here (for example, requirements for certain copper‑nickel‑tin spinodal alloys are handled in Specification B740).

Key topics and requirements

• Permitted copper alloy UNS numbers and compositional baselines for strip manufacture.
• Material forms acceptable for feedstock (cast bar, billet, slab, etc.).
• Mechanical property requirements: tensile strength, yield strength, and elongation by temper/condition.
• Available tempers and heat‑treatment/processing notes (annealed, rolled, mill‑hardened, etc.).
• Dimensional tolerances and finishing requirements (thickness, width, straightness, mass, length tolerances).
• Testing and inspection provisions referenced by the standard (including unit system handling and safety caveats for test methods).
• Reference to other ASTM specifications for alloys or special alloy classes not covered directly (e.g., B740 for some copper‑nickel‑tin alloys).

Typical use and users

Used by material suppliers, strip mills, connector and spring‑contact manufacturers, design and process engineers in the electronics and electrical interconnect industries, quality and inspection laboratories, and procurement/specification writers who require a defined baseline for copper‑alloy strip used in electrical connectors and spring contacts. The standard is applied when ordering, specifying, or accepting strip stock for high‑volume connector production.

Related standards

Normative and related references called out or commonly used alongside this specification include ASTM B740 (requirements for some copper‑nickel‑tin spinodal alloys), relevant UNS designation lists for copper alloys, and other ASTM copper/alloy product specifications that address form, composition, or special finishing. Users commonly cross‑reference UNS alloy designation tables and other ASTM product standards when selecting suitable alloys or verifying compositional limits.

Keywords

copper alloy strip, electrical connectors, spring contacts, UNS alloys, temper, tensile strength, yield strength, elongation, dimensional tolerances, ASTM B888, B888M, B740.

FAQ

Q: What is this standard?

A: ASTM B888/B888M‑25 is a specification that prescribes requirements for copper alloy strip intended for manufacture of electrical connectors and spring contacts, including allowable alloy types (UNS numbers), mechanical properties, tempers, and dimensional tolerances.

Q: What does it cover?

A: It covers material origin/form, permitted alloys (listed UNS numbers), processing routes (hot/cold working, annealing, heat treating), temper conditions, mechanical property requirements (tensile, yield, elongation), dimensional and mass tolerances, and unit system usage (SI or inch‑pound used independently). It also references other specifications for alloys outside its scope.

Q: Who typically uses it?

A: Strip producers, connector and contact manufacturers, design and process engineers in electrical/electronics manufacturing, purchasing/specification teams, and test/quality laboratories use this standard to specify and verify strip material for connector and spring‑contact production.

Q: Is it current or superseded?

A: The B888/B888M‑25 edition (designation year 2025) is the current active edition published April 1, 2025. Earlier historical editions include B888/B888M‑24, B888/B888M‑19 and prior versions; users should reference the 2025 edition for the latest requirements.

Q: Is it part of a series?

A: It belongs to ASTM’s suite of non‑ferrous metal product specifications (ASTM Committee B05 series for copper and copper alloys) and is commonly used together with related ASTM specifications and UNS alloy designation references (for example, requirements for some special copper‑nickel‑tin alloys are addressed in ASTM B740).

Q: What are the key keywords?

A: Key keywords are copper alloy strip, electrical connector strip, spring contact strip, UNS alloy, temper, tensile, yield, elongation, dimensional tolerances, ASTM B888/B888M‑25.