Application Guide 03

Automotive

Brass alloy selection for fuel systems, brake components, pneumatic connectors, and high-volume CNC — with ELV Directive compliance guidance.

ELV Directive High-Volume CNC Fuel · Brake · Pneumatic
Regulatory Context

ELV Directive & Automotive Lead

The End-of-Life Vehicles (ELV) Directive (2000/53/EC) restricts heavy metals including lead in new vehicles sold in the EU. Like RoHS, it includes a specific exemption for lead in copper alloys:

ELV Annex II, Entry 2(c): "Lead as an alloying element in copper alloys with a lead content up to 4% by weight." This mirrors RoHS Exemption 6(c) and covers leaded brass fittings used in vehicle systems.

This exemption is regularly reviewed. For new automotive platform designs (especially BEV/PHEV with long production runs), specifying lead-free brass where technically possible reduces future compliance risk. ELV Annex II exemptions have become progressively stricter over successive reviews.

CW612N advantage: With Pb 1.0–2.0% (lower end of leaded brasses) and 65% machinability, CW612N is often the preferred automotive leaded grade — less lead burden while retaining good machinability.
Volume

Machinability Matters Most

Automotive brass fittings are typically high-volume CNC or Swiss-turn parts — millions of units per year. Machinability directly impacts cycle time and tool cost.

CW617N100%
CW614N95%
CW625N72%
CW612N65%
CW724R (lead-free)80%
C27450 (lead-free)55%
Alloy Selection

Automotive Applications — Alloy Guide

AlloyMachinabilityELV/RoHSStrength (Rm)Cold WorkBest Automotive Use
CW617N100%ELV Exempt360–470 MPaModerateFuel line fittings, pneumatic connectors, high-vol CNC
CW614N95%ELV Exempt380–500 MPaLowHigh-precision turned parts, surface-critical housings
CW625N72%ELV Exempt380–500 MPaGoodPlumbing fittings, pneumatic body where cold-work needed
CW612N65%ELV Exempt360–490 MPaGoodHVAC connectors, lower-Pb preference, ductile auto parts
CW724R80%Lead-free450–600 MPaModerateBEV cooling connectors, ELV-future-proof, higher-strength
C2745055%Lead-free330–460 MPaGoodLead-free CNC parts, RoHS EEE components on vehicle
CuZn3750%Lead-free320–450 MPaExcellentStamped clips, wiring harness contacts, radiator tanks
Fuel Systems

Fuel Line Fittings

Brass is the dominant material for fuel line fittings, banjo bolts, and quick-connect bodies due to its machinability and corrosion resistance to petrol, diesel, and biofuel blends.

CW617N is the standard: 100% machinability for million-part runs, suitable for Zn-based fuel environments. For hybrid/BEV applications with alternative fluids, confirm compatibility.

Hydrogen caution: Pure copper (C11000) or stainless steel is preferred for high-pressure hydrogen fuel systems — brass can be susceptible to hydrogen embrittlement at high pressures.
Brake & Pneumatic

Pneumatic Connectors

Pneumatic brake system connectors, air dryer fittings, and ABS valve bodies are high-volume machined brass parts. Dimensional precision and seal integrity are paramount.

CW617N and CW625N are both used: CW617N for maximum throughput, CW625N where slightly better ductility is needed for crimping or deformation-fit connections.

Pressure rating: Always verify that the selected alloy and temper meet the pressure rating required by the pneumatic specification (typically SAEJ844 or ISO 8434-6).
BEV & Future-Proofing

Electric Vehicle Systems

Battery electric vehicles create new demands: thermal management fittings (coolant loops), high-voltage busbars, and charging connectors. Lead-free grades are preferred for BEV platforms with 10–15 year production horizons.

CW724R: Lead-free, higher strength (Rm 450–600 MPa), DZR-qualified — ideal for coolant fittings. C11000: For busbars and battery terminal connections.

Design for compliance: With ELV exemption reviews tightening, lead-free specs on new BEV platforms protect against future rework costs.
Automotive Brass

High-volume precision. ELV-compliant.

Brassland supplies automotive-grade brass CNC components with PPAP-ready documentation, ELV declarations, and EN 10204 3.1 material certificates.

Discuss Your Program CW617N Datasheet
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Electrical & Electronics
RoHS, conductivity, connectors
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HVAC & Refrigeration
Refrigerant compatibility, valve bodies
FAQ

Automotive brass — common questions

Which brass alloy is used for automotive fuel and brake fittings?
Free-machining leaded brasses CW617N, CW612N and CW625N are the workhorse alloys for fuel-system fittings, brake-line unions and connectors — high machinability with good strength, and compliant under the ELV Directive. Where a lead-free part is required, CW724R silicon brass is used.
Are leaded brass automotive parts ELV compliant?
Yes. The EU End-of-Life Vehicles Directive 2000/53/EC, Annex II, Entry 2(c) permits up to 4% lead by weight in copper alloys used in vehicles. Lead-free CW724R is available where a customer wants to avoid the exemption entirely.
What documentation do automotive customers receive?
EN 10204 3.1 mill certificates, IMDS material data and PPAP-capable documentation under our ISO 9001, 14001 and 45001 systems. We are not IATF 16949 certified; final functional validation and approval remain with the vehicle or system manufacturer. See RoHS and REACH status.
Which alloy is used for EV and high-voltage connector parts?
Current-carrying contacts use high-conductivity C11000 copper (about 100% IACS), while structural connector bodies use machinable brass — the choice depends on whether conductivity or machinability drives the part.
From Guide to Production

Need automotive parts made?

This guide covers alloy selection. To have components machined to your drawing, see the matching manufacturing pages:

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 alloy database — composition & properties
European Copper Institute
Copper Alliance EU — alloy designation system
MatWeb
Independent material property database
SteelNumber.com
EN material designation cross-reference
CEN / CENELEC
EN 12164, EN 12165, EN 12167, EN 12420
ASTM International
ASTM B16, B124, B283, B371 specifications
ISO 6509-1:2014
Dezincification test method (CuCl₂)
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)
WRAS (UK)
Water Regulations Advisory Scheme approval search
NSF/ANSI/CAN 61
Drinking water system components (US/CA)
Brassland — Standards Guide
Plain-English explainer for every standard above

Last reviewed: May 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.