Overview
T3 Copper is a commercial pure copper grade specified under Chinese standards and is commonly used in applications requiring good electrical conductivity, thermal conductivity, corrosion resistance, formability, and economic performance. Compared with T1 and T2 copper, T3 contains slightly lower copper purity but still provides excellent conductivity for most industrial and electrical applications.
T3 copper is widely used in:
- Electrical Components
- Conductive Connectors
- Busbars
- Copper Plates
- Transformer Parts
- Heat Exchange Equipment
- Industrial Fabrications
- Architectural Applications
Due to its favorable balance between performance and cost, T3 is widely used in general electrical and industrial manufacturing.
Material Specification
| Property | Value |
|---|---|
| Material Designation | T3 Copper |
| Chinese Standard | GB/T 5231 |
| Material Family | Pure Copper |
| Copper Purity | ≥99.70% |
| Density | 8.89 g/cm³ |
| Magnetic Property | Non-Magnetic |
| Typical Supply Condition | Annealed, Half-Hard, Hard |
| Standard Forms | Sheet, Plate, Rod, Bar, Tube, Wire |
Chemical Composition
| Element | Content (%) |
|---|---|
| Copper + Silver (Cu+Ag) | ≥99.70 |
| Bismuth (Bi) | ≤0.002 |
| Antimony (Sb) | ≤0.005 |
| Arsenic (As) | ≤0.005 |
| Iron (Fe) | ≤0.010 |
| Lead (Pb) | ≤0.010 |
| Sulfur (S) | ≤0.010 |
| Oxygen (O) | Controlled |
The slightly lower purity compared with T1 and T2 contributes to reduced material cost while maintaining excellent conductivity.
Mechanical Properties
Annealed Condition
| Property | Value |
|---|---|
| Tensile Strength | 200–240 MPa |
| Yield Strength | 50–90 MPa |
| Elongation | 35–50% |
| Hardness | 40–65 HB |
| Elastic Modulus | 117 GPa |
Cold Worked Condition
| Property | Value |
|---|---|
| Tensile Strength | 280–420 MPa |
| Yield Strength | 220–380 MPa |
| Hardness | 80–125 HB |
Physical Properties
| Property | Value |
|---|---|
| Density | 8.89 g/cm³ |
| Melting Point | 1083°C |
| Thermal Conductivity | 370–390 W/m·K |
| Electrical Conductivity | 97–99% IACS |
| Electrical Resistivity | 0.0175–0.0180 μΩ·m |
| Thermal Expansion Coefficient | 16.8 × 10⁻⁶/K |
| Specific Heat Capacity | 385 J/kg·K |
Electrical Conductivity
| Material | Conductivity (% IACS) |
|---|---|
| T1 Copper | 100+ |
| T2 Copper | 100 |
| T3 Copper | 97–99 |
| Aluminum 6061 | 40 |
| Brass C360 | 28 |
T3 still provides excellent conductivity for most power transmission and electrical applications.
Thermal Conductivity
| Material | Thermal Conductivity (W/m·K) |
|---|---|
| T1 Copper | 385–395 |
| T2 Copper | 390 |
| T3 Copper | 370–390 |
| Aluminum 6061 | 167 |
| Stainless Steel 304 | 16 |
The high thermal conductivity makes T3 suitable for cooling systems and heat transfer equipment.
Corrosion Resistance
| Environment | Performance |
|---|---|
| Indoor Environment | Excellent |
| Dry Atmosphere | Excellent |
| Fresh Water | Excellent |
| Marine Atmosphere | Good |
| Salt Water | Moderate |
| Industrial Environment | Good |
T3 copper naturally forms a protective oxide film that enhances corrosion resistance.
Recommended surface treatments:
- Tin Plating
- Nickel Plating
- Silver Plating
- Gold Plating
- Electropolishing
- Protective Coatings
Weldability
| Welding Process | Rating |
|---|---|
| TIG Welding | Excellent |
| MIG Welding | Excellent |
| Resistance Welding | Excellent |
| Brazing | Outstanding |
| Soldering | Outstanding |
T3 offers excellent joining performance for electrical and industrial assemblies.
Machinability
| Process | Rating |
|---|---|
| CNC Turning | Good |
| CNC Milling | Fair |
| Drilling | Good |
| Grinding | Good |
| Stamping | Excellent |
| Forming | Excellent |
Machinability Comparison
| Material | Machinability |
|---|---|
| Brass C360 | Excellent |
| T3 Copper | Fair |
| T2 Copper | Fair |
| C110 Copper | Fair |
| Aluminum 6061 | Excellent |
Like other pure copper grades, T3 requires sharp tooling and proper cutting parameters.
Heat Treatment
Stress Relief Annealing
| Parameter | Value |
|---|---|
| Temperature | 200–300°C |
| Cooling Method | Air Cool |
Full Annealing
| Parameter | Value |
|---|---|
| Temperature | 400–650°C |
| Cooling Method | Air Cool |
Heat Treatability
| Property | Performance |
|---|---|
| Hardening by Heat Treatment | No |
| Cold Work Strengthening | Yes |
| Annealing Response | Excellent |
T3 gains strength through cold deformation rather than heat treatment.
International Equivalent Grades
| Standard | Equivalent Grade |
|---|---|
| GB/T (China) | T3 |
| ASTM (USA) | Commercial Pure Copper |
| EN (Europe) | Cu-DHP / Similar Grade |
| DIN (Germany) | Similar Commercial Copper Grade |
| JIS (Japan) | Comparable Pure Copper Grade |
| ISO | Commercial Copper |
Note: T3 does not have a direct one-to-one international equivalent like T2 (C11000).
Available Forms
| Product Type | Availability |
|---|---|
| Sheet | Yes |
| Plate | Yes |
| Round Bar | Yes |
| Flat Bar | Yes |
| Tube | Yes |
| Wire | Yes |
| Busbar | Yes |
| Copper Foil | Yes |
Typical Applications
Electrical Industry
- Busbars
- Grounding Components
- Electrical Connectors
- Conductive Assemblies
Power Equipment
- Transformer Components
- Distribution Equipment
- Electrical Hardware
Thermal Management
- Heat Exchangers
- Cooling Systems
- Thermal Conductors
Construction Industry
- Architectural Copper
- Decorative Panels
- Roofing Systems
Industrial Manufacturing
- Copper Fabrications
- Conductive Parts
- General Engineering Components
Consumer Products
- Electrical Appliances
- Household Equipment
- Decorative Copper Products
Manufacturing Characteristics
| Manufacturing Process | Rating |
|---|---|
| CNC Machining | Good |
| Stamping | Outstanding |
| Deep Drawing | Outstanding |
| Welding | Excellent |
| Brazing | Outstanding |
| Soldering | Outstanding |
| Electroplating | Excellent |
Advantages
High Electrical Conductivity
Suitable for most industrial electrical applications.
Excellent Thermal Conductivity
Provides efficient heat transfer performance.
Good Corrosion Resistance
Suitable for indoor and outdoor environments.
Outstanding Formability
Excellent for stamping and forming operations.
Easy Fabrication
Supports welding, brazing, and soldering.
Economical
Lower material cost than higher-purity copper grades.
Limitations
Lower Conductivity Than T1 and T2
Not ideal for ultra-high conductivity applications.
Moderate Machinability
More difficult to machine than brass alloys.
Soft Material
Limited structural strength.
Limited Wear Resistance
Not recommended for severe wear environments.
Comparison with Other Copper Grades
| Property | T3 | T2 | T1 | C110 |
|---|---|---|---|---|
| Copper Purity | ≥99.70% | ≥99.90% | ≥99.95% | ≥99.90% |
| Conductivity | 97–99% IACS | 100% IACS | 100+% IACS | 100% IACS |
| Thermal Conductivity | Excellent | Outstanding | Outstanding | Outstanding |
| Cost | Lower | Moderate | Higher | Moderate |
| Electrical Performance | Excellent | Outstanding | Outstanding | Outstanding |
Comparison with Conductive Materials
| Material | Electrical Conductivity | Thermal Conductivity |
|---|---|---|
| T3 Copper | 97–99% IACS | 370–390 W/m·K |
| T2 Copper | 100% IACS | 390 W/m·K |
| T1 Copper | 100+% IACS | 385–395 W/m·K |
| Aluminum 6061 | 40% IACS | 167 W/m·K |
| Stainless Steel 304 | 2% IACS | 16 W/m·K |
Available Surface Finishes
Raw Finishes
- Mill Finish
- Bright Finish
- Annealed Finish
Functional Finishes
- Precision Machined Finish
- Brushed Finish
- Polished Finish
Conductive Finishes
- Tin Plating
- Silver Plating
- Gold Plating
- Nickel Plating
Frequently Asked Questions (FAQ)
What is T3 copper?
T3 is a commercial pure copper grade with good electrical conductivity and corrosion resistance used in electrical and industrial applications.
What is T3 copper used for?
Typical applications include:
- Busbars
- Electrical Components
- Transformer Parts
- Heat Exchangers
- Conductive Assemblies
What is the copper content of T3?
T3 contains a minimum copper content of approximately 99.70%.
What is the difference between T3 and T2 copper?
| Property | T3 | T2 |
|---|---|---|
| Copper Purity | Lower | Higher |
| Conductivity | Slightly Lower | Higher |
| Cost | Lower | Higher |
Is T3 suitable for electrical applications?
Yes. T3 provides excellent conductivity for most electrical equipment and power distribution systems.
Can T3 copper be welded?
Yes. T3 offers excellent weldability, brazability, and solderability.
Why choose T3 copper?
Because it combines:
- Good Electrical Conductivity
- Excellent Thermal Conductivity
- Good Corrosion Resistance
- Easy Fabrication
- Lower Cost
Is T3 better than T2?
T2 offers higher conductivity, while T3 offers a more economical solution for general-purpose applications.
Does GCNOV provide custom manufacturing services for T3 copper?
Yes. GCNOV provides:
- CNC Machining
- Copper Fabrication
- Busbar Manufacturing
- Electrical Component Production
- Surface Plating
- Prototype Development
- Low-Volume Production
- Mass Production