Free-Machining Copper — Tellurium

C14500

Tellurium Copper — CuTeP / ASTM B301

Copper conductivity with brass-like machinability. 0.4–0.7% tellurium forms chip-breaking inclusions that lift machinability to 85% — versus ~20% for pure copper — while keeping 93% IACS electrical conductivity. The grade of choice for machined electrical components. EN equivalent: CW118C (CuTeP).

⚡ 93% IACS Conductivity
⚙️ 85% Machinability
✅ RoHS — No Exemption
📋 ASTM B301
🌍 ≡ CW118C
93%
IACS electrical conductivity
85%
Machinability — vs ~20% for pure Cu
0.4–0.7%
Tellurium — chip-breaking inclusions
RoHS ✓
No exemption required
Chemical Composition

C14500 — ASTM B301 Limits

Weight %. Tellurium inclusions break chips without seriously degrading conductivity; a trace of phosphorus deoxidizes the melt.

ElementSymbolMin %Max %Typical %
Copper (incl. Ag)Cu99.299.699.4
TelluriumTe0.400.700.55
PhosphorusP0.0040.0120.008
Copper (Cu)
~99.4%
Tellurium
~0.55%
Mechanical Properties

Typical for rod (varies by temper)

PropertyConditionValueUnit
Tensile Strengthsoft → hard230–400MPa
Yield Strengthsoft → hard70–350MPa
Elongationby temper8–45%
Electrical Conductivityannealed~93% IACS
Thermal Conductivity~355W/(m·K)
Machinabilityvs C36000 = 10085%
Density8.94g/cm³
Melting Rangesolidus–liquidus~1050–1075°C
Typical Applications
  • Machined electrical connectors, terminals, and contact pins
  • Resistance-welding electrodes and torch/plasma tips
  • EV charging and busbar hardware machined to drawing
  • Data-center and switchgear current-carrying components
  • Heat-sink and thermal parts needing machinability plus conductivity
Why choose C14500?

Copper conductivity, screw-machine productivity

  • 85% machinability — tellurium inclusions break chips; pure copper rates only ~20%
  • 93% IACS — gives up just 7% conductivity versus C11000 for a 4× machining gain
  • ASTM B301 standardised — the recognised free-machining copper for rod, bar and shapes
  • Lead-free and RoHS compliant — no exemption needed, unlike leaded copper C18700
  • EN twin: CW118C — CuTeP on European drawings, same metallurgy
RoHS & Compliance

Compliance Status

RoHS
✓ Fully Compliant
No lead addition — tellurium and phosphorus are not restricted substances.
Conductivity Trade-Off
93% IACS vs 100% for C11000
For maximum conductivity busbars, stay with C11000 and accept slower machining; for complex machined geometry, C14500 usually wins overall.
Pure copper alternative
C11000 — Cu-ETP, 100% IACS
International Equivalents

C14500 Cross-Reference

StandardDesignation
UNS / ASTM (USA)C14500 — ASTM B301
EN — equivalentCW118C / CuTeP
Related pure copperC11000 / Cu-ETP
Trade nameTellurium Copper / Te-Cu
C14500 conductivity is quoted for the annealed condition; cold-worked tempers trade a little conductivity for strength. State both the temper and the minimum %IACS your application needs on the drawing.
← Pure copper
C11000
Cu-ETP — 100% IACS, ~20% machinability
Free-machining brass →
C36000
The 100% machinability benchmark
↑ All alloys
Materials Library
Frequently Asked Questions

C14500 — common questions

What is C14500 tellurium copper?

C14500 is free-machining copper per ASTM B301 — 99.2–99.6% copper with 0.4–0.7% tellurium and a trace of phosphorus. The tellurium forms inclusions that break chips, lifting machinability to 85% (versus ~20% for pure copper) while retaining 93% IACS electrical conductivity.

When should I choose C14500 over pure copper (C11000)?

Choose C14500 whenever the part has real machined geometry — threads, cross-holes, grooves, small diameters. The 7% conductivity penalty versus C11000 is usually invisible in service, while cycle times, tool life, and surface finish improve dramatically. Keep C11000 for simple high-current busbars where every %IACS counts.

What is the EN (CW) equivalent of C14500?

The EN designation is CW118C (CuTeP) — the same tellurium-copper metallurgy. Bar stock typically certifies to either designation; we confirm certificate wording at quotation.

Can Brassland machine C14500 parts?

Yes — C14500 suits our sliding-head CNC and Swiss-type machines well, and is our recommended grade for machined electrical components such as connectors, terminals, and welding-torch parts. Parts are made to your drawing; send it for a quote within 24 hours.

C14500 machined in Jamnagar

Free-machining copper for electrical components — 93% IACS, made 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 C14500 alloy datasheet — composition & properties
Wieland Concast
C14500 tellurium copper — producer datasheet
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.