High Conductivity CuCrZr Plate for Welding & EDM Material selection for resistance welding, EDM tooling and semiconductor cooling components

 

Publication Date: July 23, 2026
Author: Hu Yanwei, Cymber Metal Technical Expert

Quick answer: High conductivity CuCrZr plate is a precipitation-hardenable copper-chromium-zirconium alloy commonly associated with UNS C18150 and CW106C/CuCr1Zr. It retains much of copper’s electrical and thermal conductivity while providing higher strength, improved wear resistance and better resistance to softening than high-purity copper. Buyers should specify the governing standard, heat-treatment condition, minimum conductivity, hardness or strength, dimensions, flatness, inspection requirements and downstream thermal cycle before placing a bulk order.

What Is High Conductivity CuCrZr Plate?

High conductivity CuCrZr plate is a copper alloy containing controlled additions of chromium and zirconium. These alloying elements allow the material to be strengthened through solution treatment, cold working and precipitation aging.

The result is a material that combines:

• High electrical conductivity
• High thermal conductivity
• Higher strength than pure copper
• Improved dimensional stability
• Better resistance to softening at elevated temperatures
• Better wear performance under repeated mechanical and thermal loading

CuCrZr is commonly considered for resistance-welding tooling, electrical contacts, EDM electrodes, semiconductor equipment, heat-transfer components and precision-machined conductive parts.

Buyers comparing different copper product forms can begin with Cymber Metal’s broader range of copper plate options.

Is CuCrZr the Same as C18150?

UNS C18150 is one of the most commonly requested chromium-zirconium copper grades. In European specifications, buyers may also encounter designations such as CW106C or CuCr1Zr.

These designations are often used for similar alloy families, but they should not automatically be treated as identical.

A purchase specification should identify:

• The exact grade designation
• The governing material standard
• Chemical composition limits
• Product form
• Heat-treatment condition
• Minimum conductivity
• Required mechanical properties
• Test and certification requirements

C18150 should also not be confused with C18200. C18200 is commonly classified as chromium copper, while C18150 includes a controlled zirconium addition. The two alloys may have similar application areas, but substitution should require an engineering review.

Buyers sourcing this grade can review Cymber Metal’s C18150 copper information together with the project-specific drawing and material standard.

Typical CuCrZr Plate Properties

CuCrZr properties depend strongly on composition, product form, cold work, aging treatment, plate thickness and any later heating operation.

The following values are general industry reference ranges, not contractual guarantees:

For reference:

100% IACS corresponds to approximately 58 MS/m at 20°C.

Therefore, a CuCrZr plate measured at 80% IACS would have an electrical conductivity of approximately 46.4 MS/m at the same reference temperature.

This calculation is useful for unit conversion, but the purchase order should state which unit controls acceptance.

Why Is CuCrZr Used for Welding Applications?

In this context, “welding applications” usually refers to resistance-welding tooling and current-carrying components—not to CuCrZr being used as an ordinary structural welding plate.

Common applications include:

• Resistance-welding electrode holders
• Spot-welding electrode components
• Seam-welding wheels
• Welding fixtures
• Current-carrying arms
• Backing bars
• Conductive clamping components
• Water-cooled welding tooling

These components must carry high electrical current while resisting deformation, wear and repeated thermal cycling.

Pure copper may offer higher conductivity, but it can soften or deform more readily under pressure and elevated temperature. CuCrZr provides a useful balance between conductivity and mechanical stability.

What should be specified for welding tooling?

Buyers should define:

• C18150, CW106C or another exact grade
• Required heat-treatment condition
• Minimum electrical conductivity
• Hardness or tensile-property range
• Electrode or tooling geometry
• Contact-face dimensions
• Surface-finish requirements
• Cooling-channel dimensions
• Thread and connection requirements
• Permitted dimensional change after processing
• Final inspection requirements

For water-cooled welding components, the drawing should also identify:

• Coolant inlet and outlet dimensions
• Internal channel geometry
• Required working pressure
• Leak-test pressure and method
• Thread standard
• Sealing-surface requirements
• Cleanliness requirements

A supplier cannot determine all of these parameters from the phrase “CuCrZr welding plate” alone.

Is CuCrZr Plate Suitable for EDM Electrodes?

CuCrZr can be considered for electrical discharge machining electrodes when the application requires a combination of electrical conductivity, rigidity, wear resistance and dimensional stability.

Potential benefits include:

• Better mechanical strength than pure copper
• Reduced risk of bending in thin or extended electrode geometries
• Improved resistance to handling damage
• Good dimensional stability during electrode machining
• High electrical conductivity for effective discharge performance
• Better wear resistance in selected operating conditions

However, CuCrZr is not automatically the best EDM electrode material for every job.

The correct choice depends on:

• Workpiece material
• Roughing or finishing operation
• Electrode geometry
• Required surface finish
• Electrode wear ratio
• Discharge settings
• Flushing conditions
• Machining speed
• Electrode cost
• Dimensional accuracy

Pure copper may be preferred when maximum conductivity or a particular finish is required. Copper tungsten may be selected when arc-erosion resistance, stiffness or wear performance is more important than conductivity and material cost.

EDM users should conduct process trials when changing from an established electrode material to CuCrZr.

Why Use CuCrZr for Semiconductor Cooling?

Semiconductor manufacturing and power-electronics systems increasingly require components that can transfer heat while maintaining dimensional stability.

Possible CuCrZr applications include:

• Water-cooled base plates
• Cold-plate components
• Heat spreaders
• Power-module supports
• High-current thermal components
• Vacuum-equipment components
• Cooling manifolds
• Machined plates with internal channels
• Semiconductor process-equipment components

High-purity copper grades such as C10100 copper and C10200 copper can provide higher electrical and thermal conductivity. CuCrZr becomes attractive when the component must also resist deformation, maintain flatness or retain mechanical strength during thermal cycling.

Important semiconductor cooling requirements

A semiconductor cooling-plate RFQ may need to define:

• Minimum thermal or electrical conductivity
• Finished flatness
• Parallelism
• Surface roughness
• Cooling-channel dimensions
• Channel-position tolerances
• Joining or brazing process
• Leak-test method and acceptance criteria
• Operating pressure
• Thermal-cycle conditions
• Coolant chemistry
• Surface coating or plating
• Cleanliness and particle-control requirements
• Packaging for finished surfaces

If nickel plating, brazing, diffusion bonding or another high-temperature process will be used, the supplier should know the complete thermal cycle before confirming final material properties.

CuCrZr vs Pure Copper, Chromium Copper and Copper Tungsten

Material	Conductivity	Strength and wear	Thermal stability	Common selection reason
CuCrZr / C18150	High	Higher than pure copper	Good for a conductive copper alloy	Balanced conductivity, strength and softening resistance
C10100 or C10200	Very high	Lower than CuCrZr	More sensitive to softening and deformation	Maximum conductivity and high-purity requirements
C18200 chromium copper	High	Good	Good	Resistance-welding and electrical tooling
Copper tungsten	Moderate and composition-dependent	Very high wear and arc resistance	Strong under demanding electrical contact conditions	EDM, arcing contacts and high-wear electrodes

No material is universally superior.

The buyer should select the alloy according to the required balance among:

• Electrical conductivity
• Thermal conductivity
• Mechanical strength
• Wear resistance
• Softening resistance
• Machinability
• Joining requirements
• Inspection requirements
• Total component cost

Why Heat-Treatment Condition Matters

CuCrZr performance is created by its processing history. The words “C18150 plate” alone do not define the final conductivity, hardness or strength.

A typical production route may involve:

1. Solution treatment
2. Rapid cooling or quenching
3. Cold working, when required
4. Precipitation aging
5. Final machining or grinding

The order and parameters of these operations affect the balance between conductivity and strength.

Downstream heating can change the properties

The material may be exposed to additional heat during:

• Brazing
• Welding
• Diffusion bonding
• Hot forming
• Stress relieving
• Coating or plating
• Repeated service-temperature cycles

An uncontrolled thermal cycle can overage or soften the alloy. It may also change hardness, strength, conductivity and dimensional stability.

For this reason, buyers should tell the material supplier whether the plate will undergo a later high-temperature process.

When final properties are critical, the purchase requirement should clarify whether conductivity and hardness are to be measured:

• Before machining
• After heat treatment
• After brazing or joining
• On the finished component
• On a representative test coupon

Machining High Conductivity CuCrZr Plate

CuCrZr is generally more dimensionally stable than soft, high-purity copper, but it still requires appropriate copper-alloy machining practices.

Common considerations include:

For precision components:

• Use rigid workholding without excessive clamping pressure.
• Keep chips away from finished copper surfaces.
• Use cutting fluids compatible with the downstream cleaning process.
• Balance material removal on opposing plate surfaces.
• Confirm whether stress relief or aging occurs before final grinding.
• Plan datum surfaces before drilling cooling channels.
• Specify deburring and edge-break requirements on the drawing.
• Protect finished faces during inspection and packing.

Projects requiring finished parts can be reviewed together with Cymber Metal’s fine machining services.

Exact speeds, feeds and tool grades should be established according to the machine, plate condition, cutting tool, component geometry and required finish.

How Should Conductivity Be Tested?

A purchase order should not state only “high conductivity.”

It should define:

• Minimum accepted value
• Reporting unit: % IACS or MS/m
• Reference temperature
• Test method
• Test location
• Number of readings
• Sampling frequency
• Required calibration or reference standard
• Whether results must appear on the material certificate

Depending on the plate geometry and agreement between buyer and supplier, conductivity may be evaluated by an eddy-current method or calculated from electrical resistivity measurements.

The test method should be suitable for:

• Plate thickness
• Surface condition
• Curvature
• Temperature
• Probe frequency
• Required accuracy

Chemical composition alone does not prove conductivity. Likewise, a conductivity reading alone does not fully establish grade identity, heat-treatment condition or internal quality.

Buyers may review Cymber Metal’s published production and inspection equipment and certificate information. The exact test and document package must still be defined in the RFQ.

What Should Be Included in a Bulk CuCrZr Plate RFQ?

1. Grade and standard

Specify:

• UNS C18150, CW106C, CuCr1Zr or another exact designation
• Governing standard
• Standard edition, when contractually required
• Permitted or prohibited substitutions

Do not write only “CuCrZr,” “Class 2 copper” or “chromium zirconium copper.”

RWMA Class 2 is commonly associated with resistance-welding copper alloys, but it should not replace a complete grade and property specification.

2. Heat-treatment condition

State whether the plate is required as:

• Solution-treated
• Cold-worked
• Precipitation-hardened
• Fully heat-treated
• Rough-machined before final aging
• Ready for finish machining

If the buyer does not know the correct condition, provide the application, operating temperature and later manufacturing steps for technical review.

3. Required properties

Define measurable acceptance values for:

• Electrical conductivity
• Hardness
• Tensile strength, if required
• Yield strength, if required
• Elongation, if required
• Thermal conductivity, if contractually required

Do not combine typical website values from different tempers into a single purchasing specification.

4. Plate dimensions

Include:

• Thickness
• Width
• Length
• Thickness tolerance
• Width and length tolerance
• Flatness
• Straightness
• Parallelism
• Squareness
• Machining allowance
• Saw-cut, milled or ground condition

5. Surface and edge requirements

State:

• Mill, machined or ground finish
• Surface roughness
• Permitted scratches or dents
• Protective-film requirements
• Edge condition
• Burr limits
• Chamfer or corner radius
• Areas that must remain free from marking

6. Inspection and documentation

Depending on the application, the buyer may request:

• Material Test Certificate
• Certificate of Conformity
• Chemical composition report
• Electrical conductivity result
• Hardness report
• Tensile-test result
• Dimensional inspection report
• Ultrasonic inspection for specified thick sections
• Lot or heat traceability
• Third-party inspection
• Final-part leak test
• Cleanliness inspection

Relevant files currently made available by the company can be checked through the Cymber Metal download center.

7. Processing scope

Clarify whether the quotation is for:

• Raw plate
• Saw-cut blank
• Milled blank
• Ground plate
• Rough-machined component
• Finished component
• Drilled cooling plate
• Plated or coated component
• Pressure- or leak-tested assembly

8. Quantity and logistics

Provide:

• Number of plates
• Total estimated weight
• Trial-order quantity
• Annual demand
• Permitted quantity variation
• Packing requirements
• Maximum package weight
• Delivery destination
• Incoterm
• Required delivery timeline
• Marking and traceability requirements

Cymber Metal’s broader service capabilities can be reviewed when a project includes material supply, cutting, machining or export-related requirements.

How to Calculate CuCrZr Plate Weight

A practical density reference for CuCrZr is approximately 8.9 g/cm³.

For dimensions in millimeters:

Theoretical weight in kg = Length × Width × Thickness × 8.9 × 10⁻⁶

Example for a plate measuring 1,000 × 500 × 20 mm:

1,000 × 500 × 20 × 8.9 × 10⁻⁶ = approximately 89 kg

Actual weight can vary because of dimensional tolerances, edge condition and machining allowance.

For a bulk order, confirm whether pricing is based on theoretical weight, actual shipping weight or the input weight before machining.

How Should Buyers Compare CuCrZr Plate Quotations?

A lower price may reflect a different grade, untreated condition, wider dimensional tolerance or a reduced inspection scope. Quotations are only comparable when the technical and commercial requirements are aligned.