Solutions for Machining Pure Copper

Pure copper, which has a minimum copper content of 99.3% or higher, and is essentially unalloyed copper. It exhibits characteristics including electrical and thermal conductivity, corrosion resistance, good strength, fatigue resistance. Copper is a low-cost material that is easy to shape and  heat-treated to the desired hardness to improve the durability of machined copper parts. It offers ease of joining by a wide variety of methods, including brazing, soldering, bolding, or adhesives. 

C10100, C10200: (Oxygen Free Copper) is 99.99% Copper with 0.0005% Oxygen content. High Conductivity (OFHC) Copper characteristics are high ductility, high electrical and thermal conductivity, high impact strength, good creep resistance, ease of welding, and low volatility under high vacuum. Electrical applications: conductors, microwave tubes, transistor components, lead in wire, coaxial cables, copper to glass seals in appliances, busbars, bus conductors, and wave guides. Industrial applications: tubing, LP gas service, tubing, vacuum seals, coaxial tube, billet mold tube, and extrusion cans for powder metallurgy.

ETPC11000 | C110 | ETP C110: (Electronic Tough Pitch Copper) have a 99.9% Copper composition and .04% Oxygen. It has a low machinability rating at 20. ETP 110 is one of the most commonly used commercially pure coppers.  C11000 copper has one of the highest electrical conductivity ratings, in excess of 100%IACS. Some applications include electrical; telecommunications; architectural; and antimicrobial.

Typical Machining Concerns

Pure copper is very difficult to machine due to high plasticity and toughness. Tool wear is very high and chip formation is poor. Chip compression is substantial subjecting the cutting edge to large mechanical loads. Long tubular chips form which are difficult to manage and remove. There is also a risk of built-up edge which can lead to a poor machined surface finish.

Reduced tool life due to wear and chip control issues make automatic machining - high volume production runs - difficult to accomplish.

Tooling is Key to Success

Coolant Through Holder + UC1 or TM4 coated carbide

High quality part surface finish is obtained:  Use a coolant through holder and applying the appropriate insert and cutting conditions. The coolant through holder helps remove the chips from the part & cutting area. 

Stable machining & chip generation: Apply the best insert grade and chipbreaker combination. Chip control issues are eliminated by adding a Y-axis toolholder to the operation. The chips drop down away from the cutting area with the help of gravity.  Utilize on all vertical gang stations. 

See below details for front turning as well as ID boring operations.

Front Turning  - Tough Pitch Copper   

Apply UC1, a highly pure - fine diamond particle coated carbide grade to achieve excellent wear resistance and adhesion resistance. The appropriate chip breaker will provide additional chip control.

• Small DOC and low feed rate to reduce chip thickness-  select AM3 chipbreaker
• Larger DOC and higher feed rate - select ZP chipbreaker to prevent chip tangling

 Cutting Parameters

Front Turning - Oxygen Free Copper

Stable machining: apply TM4, a thin TiN-TiCN-TiN coated carbide grade with a balance of toughness, adhesions resistance, and sharp cutting edges. Select the appropriate chipbreaker -  CL, AM3, or ZP.

Tool life can be extended by applying UC1 grade with a AM3 or ZP chipbreaker.

 Cutting Parameters

Case Studies

ID Boring - Pure Copper 

The F style chipbreakers = Evacuate chips backwards. Use right hand chipbreaker with right hand boring bars.

Cutting Parameters

Join us on Instagram

It is our commitment to partner with customers and forge a path with technological insight with superior products and performance. By working closely with manufacturers to understand the machining issues they face we deliver a true tooling solution.