ASTM B194
Standard Specification for Copper-Beryllium Alloy Plate, Sheet, Strip, and Rolled Bar
Specification for copper-beryllium alloy (C17000, C17200, C17500, C17510) plate, sheet, strip and rolled bar in solution-annealed, cold-rolled, mill-hardened and age-hardened tempers, with age-hardening capability requirements.
What ASTM B194 specifies
ASTM B194 covers the flat-rolled beryllium-copper products used for springs, contacts, connectors and mould tooling: high-strength C17000 and C17200 (about 1.6–2.0 % Be) and high-conductivity C17500/C17510 (cobalt- or nickel-bearing with about 0.2–0.6 % Be). Tempers are the solution-annealed TB00 (A), cold-rolled TD01–TD04 (1/4 H to H), mill-hardened TM00–TM08 (AM through XHMS) that need no further heat treatment, and the user-age-hardened TF00 (AT) and TH01–TH04 (1/4 HT to HT). For the heat-treatable tempers the specification defines the standard age — 600 °F (315 °C) for about 3 h from TB00 or 2 h from TD04 for C17200; 900 °F (480 °C) for C17500/C17510 — and the properties the material must reach after it: C17200 TF00 165–190 ksi (1140–1310 MPa) tensile, TH04 190–215 ksi (1310–1480 MPa). Tests cover tension, hardness, bend/formability and, for the conductivity grades, electrical resistivity.
ASTM B194 types and classes
Every designation the document defines, with the thickness it requires and the tests it imposes.
| Designation | Meaning | Requirement / test |
|---|---|---|
TB00 (A) | Solution annealed, as supplied for forming; ages to TF00. C17200 as supplied: 60–78 ksi (410–540 MPa) tensile. | Tension per ASTM E8 as supplied and after standard age |
TD04 (H) | Solution annealed and cold rolled to full hard; ages to TH04. C17200 as supplied: 100–120 ksi (690–830 MPa) tensile. | Tension per ASTM E8 as supplied and after standard age |
TF00 (AT) | TB00 aged about 3 h at 600 °F (315 °C). C17200: 165–190 ksi (1140–1310 MPa) tensile. | Tension per ASTM E8; hardness per ASTM E18 |
TH04 (HT) | TD04 aged about 2 h at 600 °F (315 °C). C17200: 190–215 ksi (1310–1480 MPa) tensile, the highest-strength copper alloy temper. | Tension per ASTM E8; hardness per ASTM E18 |
TM00–TM08 (AM–XHMS) | Mill hardened: cold rolled and aged by the producer, used as received with no further heat treatment; strength graded between the TD and TH tempers, with excellent formability at the softer end. | Tension per ASTM E8; hardness per ASTM E18 |
Tests and the drawing call-out
Tests the document imposes
- Tension test per ASTM E8/E8M as supplied and, for heat-treatable tempers, after the standard age
- Rockwell hardness per ASTM E18 (HRB / HR30T / HRC depending on temper and thickness)
- Bend / formability test for spring tempers when specified
- Electrical resistivity per ASTM B193 for C17500 / C17510
- Chemical analysis (beryllium, cobalt, nickel) per ASTM E478 or spectrographic methods
How to cite it
Drawing call-out
MATERIAL: C17200 STRIP PER ASTM B194, TEMPER TD04 (H); AGE HARDEN TO TH04 AFTER FORMING, 2 H AT 600 °FAngle brackets mark the choices the drawing must make; every finish page shows a completed example.
Heat treatments specified to ASTM B194
| Treatment | Role | Cost |
|---|---|---|
Age C17200 (Beryllium Cu) is a precipitation-hardening condition for C17200 and C17300. | Governing | $$$ |
ASTM B194 — frequently asked
Should I buy TB00 / TD04 and age, or mill-hardened?
Age after forming (TB00 to TF00, TD04 to TH04) when the part is deep-formed or coined: the annealed and cold-rolled tempers form easily and the age adds well over 100 ksi. Buy mill-hardened (TM) when the part is stamped flat or lightly bent and you want to skip heat treatment and the beryllium-handling controls that go with it.
How is the age performed?
At 600 ± 10 °F (315 °C) in a clean air or inert-atmosphere furnace, about 3 h from TB00 or 2 h from the cold-rolled tempers for C17200; C17500 and C17510 age at 900 °F (480 °C) for about 3 h. Over-ageing (longer or hotter) lowers strength but raises conductivity and stability, and is sometimes specified deliberately.
How should I specify hardness on an aged part?
Order to the tensile range in the specification (for example 190–215 ksi for TH04) and let hardness — Rockwell C, or superficial 30N / 15N on thin strip — be a lot check correlated by the supplier. Hardness alone does not distinguish TH02 from TH04 reliably on strip under about 0.5 mm.
Are there handling requirements?
Beryllium-copper is safe as a solid, but grinding, polishing, welding or heat treating that produces dust or fume requires beryllium exposure controls (the OSHA permissible exposure limit is 0.2 µg/m³ as an 8-hour average); heat treaters and machine shops need the alloy identified on the drawing and purchase order.
ASTM B194 is copyrighted by ASTM International. This page explains the document so a drawing can be read; it does not reproduce the standard. Purchase the current edition from the publisher. Official source ↗