Naval Brass — Marine Grade

C46400

Naval Brass — CuZn39Sn1 / ASTM B21

The classic marine brass — a 60/40 copper-zinc base with ~0.8% tin for corrosion resistance in seawater. Strong, wear- and galling-resistant, hot-forgeable (rated 90), and resistant to stress-corrosion cracking. No lead addition. EN equivalent: CW719R (CuZn39Sn1).

🌊 Seawater Service
🔥 90 Hot Forgeability
⚙️ ~30% Machinability
📋 ASTM B21
🌍 ≡ CW719R
~0.8%
Tin — seawater corrosion resistance
90
Hot forgeability rating
~30%
Machinability — plan slower feeds
≤0.20%
Lead (max) — no Pb addition
Chemical Composition

C46400 — ASTM B21 Limits

Weight %. The tin addition stabilises the alloy against corrosion and erosion in saline and brackish water; no lead is added.

ElementSymbolMin %Max %Typical %
CopperCu59.062.060.0
ZincZnBalance~39.2
TinSn0.501.00.8
Lead (max)Pb0.20≤0.10
IronFe0.100.05
Copper (Cu)
~60%
Zinc (Zn)
~39.2%
Tin (Sn)
~0.8%
Mechanical Properties

Typical for rod (varies by temper)

PropertyConditionValueUnit
Tensile Strengthsoft → hard380–605MPa
Yield Strengthsoft → hard170–455MPa
Elongationby temper17–45%
Machinabilityvs C36000 = 100~30%
Hot Forgeabilityvs C37700 = 10090
Density8.41g/cm³
Melting Rangesolidus–liquidus885–900°C
Typical Applications
  • Marine hardware — shafts, fasteners, fitting bodies, deck components
  • Seawater and brackish-water system components
  • Condenser and heat-exchanger tube plates and parts
  • Wear- and galling-resistant bushings, pins, and guides
  • Hot-forged marine and industrial components finish-machined to drawing
Why choose C46400?

The brass that goes to sea

  • Sn ~0.8% addition — markedly improves corrosion and erosion resistance in seawater versus plain 60/40 brass
  • Strong and galling-resistant — tensile to ~605 MPa hard; resists wear, fatigue, and stress-corrosion cracking
  • Hot forgeability 90 — forges nearly as well as forging brass, ideal for marine hardware blanks
  • No lead addition — Pb ≤0.20% max; typically low, but confirm the mill certificate for RoHS-critical orders
  • EN twin: CW719R — CuZn39Sn1 on European and ISO drawings
RoHS & Compliance

Compliance Status

RoHS
Typically Compliant — Verify Cert
No Pb addition; spec allows up to 0.20% max, above the 0.10% RoHS threshold. For RoHS-critical orders we confirm actual Pb on the Type 3.1 mill certificate.
Seawater Service
Good — Uninhibited Grade
Tin addition resists dezincification and erosion in marine service. For the most aggressive seawater duties, compare copper-nickel or inhibited grades at design stage.
Related reading
Corrosion & DZR Guide
International Equivalents

C46400 Cross-Reference

StandardDesignation
UNS / ASTM (USA)C46400 — ASTM B21
EN — equivalentCW719R / CuZn39Sn1
ISOCuZn39Sn1
Related gradeCuZn40 — Muntz metal (no Sn)
Trade nameNaval Brass (uninhibited)
⚠️ C46400 machinability is ~30% — plan for slower feeds, sharper tooling, and longer cycle times than free-cutting brass. Pricing reflects machining time; forged blanks can reduce it on heavy sections.
← Muntz cousin
CuZn40
60/40 brass without the tin addition
Lead-free forging →
CW510L
CuZn42 — hot forging lead-free
↑ All alloys
Materials Library
Frequently Asked Questions

C46400 — common questions

What is C46400 naval brass?

C46400 is the standard naval brass per ASTM B21 — roughly 60% copper, 39% zinc, and 0.5–1.0% tin. The tin addition gives it corrosion and erosion resistance in seawater, and it is strong (tensile to ~605 MPa hard), galling-resistant, and hot-forgeable. There is no lead addition.

What is the EN (CW) equivalent of C46400?

The EN equivalent is CW719R (CuZn39Sn1), which is also the ISO designation. The same metallurgy serves drawings written to either system; we confirm the certificate wording at quotation.

Is C46400 RoHS compliant?

Usually — there is no lead addition and typical heats run well under 0.10% Pb, but the ASTM B21 limit allows up to 0.20% max, which exceeds the RoHS threshold on paper. For RoHS-critical orders we verify the actual Pb content on the Type 3.1 mill certificate before production.

What should I expect when machining C46400?

Plan for ~30% of the free-cutting benchmark: lower speeds, positive sharp tooling, and stringier chips than leaded brass. It machines predictably but slowly — heavy sections are often cheaper hot-forged first and finish-machined. Send your drawing for a quote within 24 hours.

C46400 machined in Jamnagar

Naval brass marine components, forged and machined to your drawing. ISO 9001:2015. Quote within 24 hours.

Request a Quote
Sources & References

Verify this datasheet against the primary source

Composition ranges, mechanical properties, machinability ratings and regulatory data on this page are cross-referenced against the publishers below. Tolerances and minimum values are taken from the relevant published standard at the time of writing — for procurement specification, always reference the current published edition.

Copper Development Association
CDA C46400 alloy datasheet — composition & properties
ASTM B21/B21M
Naval Brass Rod, Bar, and Shapes
MatWeb
Independent material property database — by temper
European Copper Institute
Copper Alliance EU — EN alloy designation system
SteelNumber.com
EN material designation cross-reference
CEN / CENELEC
EN 12164, EN 12165, EN 12167 — EN rod standards
EU RoHS Directive 2011/65
Annex III Exemption 6(c) — valid to 30 Jun 2027
ECHA REACH SVHC List
Lead is on the candidate list (Article 33)
NSF/ANSI/CAN 61
Drinking water system components (US/CA)
Brassland — Standards Guide
Plain-English explainer for every standard above

Last reviewed: June 2026. EN/ISO/ASTM standards are updated periodically. This datasheet reflects the editions listed; for safety-critical or contract-critical applications, always 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.