Mass %, Copper Development Association (C69310) and JIS H3250:2015 Table 3 (C6931) — the same ranges; JIS adds the bismuth and cadmium limits. CDA: copper includes silver, nickel includes cobalt, copper plus the named elements at least 99.5 %. Typical column = nominal analysis (76.0 Cu – 3.0 Si – 0.5 Sn – 0.08 P).
| Element | Symbol | Min % | Max % | Typical % |
|---|---|---|---|---|
| Copper | Cu | 74.0 | 79.0 | 76.0 |
| Silicon | Si | 2.6 | 3.4 | 3.0 |
| Tin | Sn | 0.30 | 0.7 | 0.5 |
| Phosphorus | P | 0.04 | 0.15 | 0.08 |
| Lead | Pb | — | 0.09 | <0.09 |
| Iron | Fe | — | 0.10 | — |
| Nickel | Ni | — | 0.20 | — |
| Manganese | Mn | — | 0.10 | — |
| Bismuth (JIS) | Bi | — | 0.05 | — |
| Cadmium (JIS) | Cd | — | 0.0075 | <0.0075 |
| Zinc | Zn | Balance | ~20 | |
| Property | Condition | Value | Unit |
|---|---|---|---|
| Tensile Strength | F — BE-F ≥6 mm, BD-F 1–110 mm | ≥450 | N/mm² (MPa) |
| Elongation | F — same product forms | ≥5 | % |
| Hardness | F — alternative acceptance (Table 4, note a) | ≥110 | HV |
| Density | CDA | 8.3 | g/cm³ |
| Electrical Conductivity | CDA | 8 | %IACS |
| Thermal Conductivity | CDA | 38 | W/(m·K) |
| Thermal Expansion | CDA, 20–300 °C | 18.7 | ×10⁻⁶/K |
| Melting Range | solidus–liquidus | 850–900 | °C |
| Modulus of Elasticity | CDA | 105 | GPa |
| Machinability | CDA rating, C36000 = 100 | 70 | index |
Fabrication ratings on the CDA scale; temperatures converted from °F.
| Process | CDA rating |
|---|---|
| Machinability rating | 70 (C36000 = 100) |
| Hot forming | Excellent |
| Forgeability rating | 95 (C37700 = 100) |
| Cold working | Poor |
| Annealing | 500–600 °C |
| Soldering | Excellent |
| Brazing | Good |
| Welding | Good for oxyacetylene, gas-shielded arc, coated metal arc, spot, seam and butt welding |
| Standard | Designation |
|---|---|
| UNS (USA) | C69310 — Copper Development Association |
| JIS (Japan) — same ranges | C6931 — JIS H3250 (BE / BD rod) |
| EN (Europe) | none — the EN number CW724R belongs to the tin-free C69300 |
| Tin-free sibling | C69300 / JIS C6932 / EN CW724R |
C69310 is a lead-free silicon brass with tin: 74.0–79.0 % copper, 2.6–3.4 % silicon, 0.30–0.7 % tin, 0.04–0.15 % phosphorus and at most 0.09 % lead, balance zinc (Copper Development Association). JIS H3250 lists the same ranges as C6931, with bismuth up to 0.05 % and cadmium up to 0.0075 %. Rod in condition F must reach 450 N/mm² tensile strength and 5 % elongation, or 110 HV where hardness is applied.
The tin. C69310 (JIS C6931) requires 0.30–0.7 % tin; C69300 (JIS C6932, EN CW724R) limits tin to 0.20 %. Their copper and silicon ranges are close — 74–79 % and 2.6–3.4 % for C6931, 74–78 % and 2.7–3.4 % for C6932 — and JIS H3250 sets the same rod minimums for both. In jet-stream erosion tests the tin grade wears less than C3604 and about as much as CAC406 bronze.
Yes. Lead is limited to 0.09 %, below the 0.1 % RoHS threshold for lead in a homogeneous material, so no exemption is needed. The same limit keeps the material within NSF/ANSI 372, which allows a weighted average of 0.25 % lead on wetted surfaces; certification of the finished product, for example to NSF/ANSI 61, remains with the product maker.
No. The tin grade is standardised as C69310 (UNS) and C6931 (JIS H3250); the European number CW724R belongs to the tin-free C69300. C69310 always contains at least 0.30 % tin, above C69300’s 0.20 % maximum, so a drawing that names C69300 or CW724R needs approval before C69310 is supplied.
Faucet parts in fast-flowing water, water meter cases, faucet fittings and sprinkler heads. Hot forming is rated excellent and all common welding processes good; the machinability rating is 70 (C36000 = 100).
Yes — turned and milled to your drawing in Jamnagar. Whether bar certified to C69310 or JIS C6931 is available for your quantity is confirmed at quotation; every shipment carries an EN 10204 3.1 mill certificate. Series lead time is 3–5 weeks from the approved drawing.
JIS H 3250 C 6931 BD-F (drawn rod, as manufactured) or UNS C69310. Name C69310 / C6931 explicitly — a drawing that says only “silicon brass”, C69300 or CW724R does not call for the tin addition.Primary source: JIS H3250 — Copper and copper alloy rods and bars (JISC).
Lead-free brass parts turned, milled and inspected in Jamnagar. ISO 9001:2015. Quote within 24 hours.
Request a QuoteComposition limits, physical properties and fabrication ratings are taken from the Copper Development Association datasheet; the rod minimums from JIS H3250. For procurement specification, always reference the current published edition of the standard.
Last reviewed: September 2026. Composition limits are those published by the Copper Development Association and tabulated in JIS H3250:2015; JIS H3250 was revised in 2021. Nominal values are not specification limits. For safety-critical or contract-critical applications, verify against the current published edition of the standard. For project-specific deviations or supplier-specific composition windows, request a Type 3.1 mill certificate (EN 10204) with your order.
Brassland machines C69310 into brass turned parts and CNC machined components to your drawing in Jamnagar, India, including precision turned brass components on 28+ Swiss-type lathes, with an EN 10204 3.1 certificate on every shipment.