W/mK
IACS
copper content
rating
Copper C110 CNC Machining: Maximum Thermal and Electrical Performance
Copper C110 is 99.9% pure copper. It has the highest thermal conductivity (391 W/mK) and electrical conductivity (101% IACS) of any common engineering metal. Nothing else comes close.
Also called ETP copper (Electrolytic Tough Pitch) or C11000, this is the material you use when heat or electricity needs to move through a part as fast as possible. Heat sinks, bus bars, electrodes, RF waveguides — if the job is thermal or electrical, copper C110 is the answer.
The trade-off is machinability. Copper C110 rates just 20% on the machinability scale (compared to brass 360 at 100%). It is soft, gummy, and sticks to cutting tools. Long, stringy chips clog up machines. You need sharp tools, high speeds, and a machinist who knows copper.
RivCut machines copper C110 every week. We have the tooling, the coolant strategy, and the experience to deliver clean, tight-tolerance copper parts. From simple bus bars to complex multi-fin heat sinks, we handle it.
Copper C110 Material Properties
Here are the numbers that matter when you design with copper C110.
| Property | Value | What It Means |
|---|---|---|
| Tensile Strength | 32 ksi (annealed) / 50 ksi (hard) | Moderate — not a structural material |
| Yield Strength | 10 ksi (annealed) / 40 ksi (hard) | Varies widely with temper |
| Hardness | Rockwell F40 (soft) to B50 (hard) | Soft material — easy to deform |
| Thermal Conductivity | 391 W/mK | Best of any common metal — 2.3x aluminum |
| Electrical Conductivity | 101% IACS | The standard all metals are measured against |
| Density | 0.323 lb/in³ (8.94 g/cm³) | Heavy — 3.3x aluminum, similar to brass |
| Purity | 99.9% copper | Trace oxygen present (ETP grade) |
| Machinability | 20% (of brass 360) | Challenging — needs sharp tools, expert setup |
| Corrosion Resistance | Good | Resists fresh water, but oxidizes in air |
| Melting Point | 1,981°F (1,083°C) | Higher than aluminum, lower than steel |
Copper Grades: C110 vs C101 vs C145
Not all copper is the same. Here are the three grades you will see most in CNC machining and when to use each one.
| Property | C110 (ETP) | C101 (OFE) | C145 (Tellurium) |
|---|---|---|---|
| Purity | 99.9% | 99.99% | 99.5% |
| Electrical Conductivity | 101% IACS | 101% IACS | 93% IACS |
| Thermal Conductivity | 391 W/mK | 391 W/mK | 355 W/mK |
| Machinability | 20% | 20% | 85% |
| Oxygen Content | ~0.04% | <0.001% (oxygen-free) | ~0.01% |
| Best For | Bus bars, heat sinks, electrodes | Vacuum, superconductors, semiconductor | Complex machined parts needing good conductivity |
| Cost | $$ | $$$$ | $$$ |
Key takeaway: Use C110 for most thermal and electrical applications. Use C101 only when you need oxygen-free purity for vacuum or semiconductor work. Use C145 when you need easier machining and can accept slightly lower conductivity.
Copper C110 vs Other CNC Materials
Should you use copper C110 or something else? Here is the side-by-side comparison.
| Property | Copper C110 | Aluminum 6061-T6 | Brass 360 | Stainless 304 |
|---|---|---|---|---|
| Thermal Conductivity | 391 W/mK | 167 W/mK | 115 W/mK | 16 W/mK |
| Electrical Conductivity | 101% IACS | 43% IACS | 26% IACS | 2.5% IACS |
| Machinability | 20% | 90% | 100% | 45% |
| Tensile Strength | 32–50 ksi | 45 ksi | 58 ksi | 75 ksi |
| Density | 0.323 lb/in³ | 0.098 lb/in³ | 0.307 lb/in³ | 0.289 lb/in³ |
| Typical Part Cost | $95–$400 | $65–$250 | $75–$300 | $100–$400 |
| Best For | Heat sinks, bus bars, electrodes | Brackets, housings, frames | Fittings, valves, gears | Shafts, food equipment |
Choose copper C110 when thermal or electrical performance is your top priority. For general-purpose parts, brass 360 machines 5x faster and costs less. Aluminum 6061-T6 is 3.3x lighter and much cheaper to machine if you don't need copper's conductivity.
Get a Copper C110 Quote in Minutes
Upload your CAD file. Select copper C110. See your price instantly with lead time and finish options.
Upload CAD for Instant QuoteIndustries That Use CNC Machined Copper C110
Copper C110 goes where heat and electricity matter most. Here are the top six industries.
Power Electronics & EV
Bus bars for battery packs, power inverters, and charging stations. Copper C110 carries hundreds of amps with minimal resistance. Critical for EV drivetrains and energy storage systems.
Semiconductor Equipment
Electrodes, cold plates, and heat exchangers for wafer processing. Copper C110 pulls heat away from chips and chambers faster than any other metal. Used in etching, deposition, and testing.
RF & Telecom
Waveguides, antenna components, and RF shielding enclosures. Copper C110's 101% IACS conductivity minimizes signal loss. Critical for 5G infrastructure and radar systems.
Thermal Management
Heat sinks for high-power LEDs, laser diodes, and power modules. Multi-fin copper heat sinks move 2.3x more heat than aluminum equivalents. Used when air cooling must handle extreme watts.
Welding & EDM
EDM electrodes and resistance welding tips. Copper C110 conducts electricity into the workpiece while resisting wear at the tip. The go-to electrode material for die-sink EDM.
Aerospace & Defense
Grounding straps, bus bars, and thermal interfaces for avionics. Copper C110 meets mil-spec conductivity requirements. Used in aircraft power distribution and radar waveguide assemblies.
Design Tips for CNC Machining Copper C110
Copper C110 is tricky to machine. These tips help you get better parts at lower cost.
1 Keep Walls Thick
Copper C110 is soft. Walls under 0.060" can deflect under clamping pressure and cutting forces. Design walls at 0.080" or thicker when possible. If thin sections are needed, tell us so we can plan special fixturing.
2 Add Generous Inside Radii
Copper's gumminess means small tools clog fast. A 0.060" minimum inside corner radius lets us use larger tools at higher feeds. This cuts machine time and cost. Avoid sharp inside corners whenever your design allows.
3 Limit Depth-to-Width Ratio on Fins
Heat sink fins are common in copper C110. Keep fin height-to-gap ratio under 6:1. A fin 0.060" wide and 0.360" tall is the practical limit. Taller, thinner fins deflect during cutting and need slow feeds that add cost.
4 Specify Temper Carefully
Copper C110 comes in annealed (soft, 32 ksi tensile) and hard (50 ksi tensile) tempers. Annealed is gummier but more ductile. Hard is stiffer and machines slightly better. Tell us your temper preference when ordering.
5 Plan for Oxidation
Copper turns dark brown within weeks in open air. If your part needs to stay shiny, specify a finish: clear lacquer, tin plating, or nickel plating. If conductivity matters more than looks, as-machined is fine.
Surface Finishes for Copper C110
Copper oxidizes fast. Pick a finish based on whether you care about looks, conductivity, or solderability.
- As-machined: Bright rose-gold color. Will oxidize to brown in weeks. Fine for electrodes and parts that live inside assemblies.
- Clear lacquer: Thin clear coat. Prevents oxidation for years. Does not affect thermal performance much. Good for display heat sinks.
- Tin plating: Matte silver finish. Prevents oxidation. Excellent solderability. The standard finish for bus bars and electrical contacts.
- Nickel plating: Bright silver finish. Hard wearing. Prevents oxidation. Adds a thin barrier that slightly reduces conductivity at the surface.
- Silver plating: The lowest-resistance plating. Used for RF waveguides and high-frequency contacts where every fraction of a dB matters.
- Mirror polish: High-gloss reflective surface. Used for laser mirrors and optical components. Requires careful handling after finishing.
- Passivation: Chemical cleaning to remove surface oxides. Improves solder wetting and contact resistance. Often done right before assembly.
Tolerances for CNC Machined Copper C110
Copper C110 is soft, which means extra care during clamping and cutting. But with proper fixturing, we hold the same tight tolerances as harder metals.
- General features: ±0.005" (±0.127 mm)
- Precision features: ±0.001" (±0.025 mm)
- Critical features: ±0.0005" (±0.013 mm) on request
- Surface finish: 32–125 Ra standard, 16 Ra or better on request
- Flatness: 0.001" per inch on machined surfaces
- Thread tolerance: Class 2B (standard) or Class 3B (precision)
The biggest risk with copper C110 is clamping deformation. The material is soft enough that vise jaws can leave marks or squeeze dimensions out of spec. Our machinists use soft jaws, vacuum fixtures, and light clamping pressure to keep your parts dimensionally perfect.
Need Copper C110 Parts Fast?
Upload your CAD file and get real pricing with finish, tolerance, and lead time options. Rush delivery in as few as 3 days.
Upload CAD for Instant QuoteCopper C110 CNC Machining Pricing
Copper C110 costs more to machine than aluminum or brass because of its low machinability. But the thermal and electrical performance is worth it when your design demands it.
Typical Price Ranges
- Simple bus bars and flat plates: $95–$150 per piece
- Medium-complexity heat sinks and electrodes: $150–$300 per piece
- Complex multi-fin heat sinks and waveguides: $250–$400+ per piece
- Volume discount: 10+ pieces typically 15–25% less per piece
What Drives Copper C110 Part Cost
| Factor | Lower Cost | Higher Cost |
|---|---|---|
| Complexity | Flat bus bar — 1 setup | Multi-fin heat sink — thin walls, deep pockets |
| Tolerances | Standard ±0.005" | Precision ±0.001" (needs slow feeds) |
| Finish | As-machined (free) | Silver plating, mirror polish |
| Quantity | 10+ pieces (amortized setup) | 1 piece (full setup cost) |
| Lead Time | Standard 5–7 days | Rush 3 days (expedite fee) |
Upload your CAD file for exact pricing. You get a real number in minutes, not a range.
Why RivCut for Copper C110 CNC Machining
Copper C110 is hard to machine well. Here is why teams trust RivCut with their copper parts.
- Copper-specific tooling. We use PCD-tipped and polished carbide tools designed for pure copper. Sharp edges and special coatings prevent the gummy buildup that ruins surface finish.
- Copper C110 always in stock. We keep C11000 flat bar and round bar on hand. No waiting for material. Your part goes straight into production.
- 100% made in USA. Every copper part is machined in our Union City, California facility. No overseas outsourcing.
- No minimum order. One bus bar or 5,000 electrodes. Same process, same quality.
- Expert fixturing for soft materials. Our machinists use soft jaws, vacuum chucks, and light clamping to prevent deformation. Your dimensions stay in spec.
- Free DFM review. We flag thin fins, deep pockets, and features that are expensive in copper. We suggest changes that save you money without hurting performance.
The RivCut Guarantee
If your copper C110 parts don't match your drawing, we remake them at no charge. Every dimension on your print is a promise we make. We back that with calibrated inspection and a team that takes tolerance seriously.
Related Tools & Articles
Copper C110 CNC Machining: Common Questions
Related Resources
Learn more about CNC materials and services.
Get Your Copper C110 Quote in Minutes
Upload your CAD file for instant pricing. Copper C110 always in stock. Rush delivery in as few as 3 business days. 100% made in USA.
No minimums · Free DFM review · NDA ready · Ships anywhere in the US