Copper C101 (T2)

Introduction to Copper C101 (T2)

Copper C101, also known as T2 copper or Electrolytic Tough Pitch (ETP) copper, is one of the purest forms of commercially available copper with a minimum copper content of 99.9%. It offers exceptional electrical and thermal conductivity, good ductility, and excellent formability, making it the most widely used copper grade in electrical and electronic applications.

Due to its outstanding conductivity and ease of fabrication, Copper C101 is frequently selected for CNC Machining Service applications, especially for CNC Machined Copper Parts such as electrical connectors, busbars, terminal blocks, and transformer parts across power generation, electronics, and aerospace industries.

Chemical, Physical, and Mechanical Properties of Copper C101 (T2)

Chemical Composition (Typical)

Physical Properties

Mechanical Properties (Annealed Temper)

Note: These values are representative of annealed (soft) C101 copper at room temperature. Mechanical strength increases with cold working but may reduce elongation.

Key Characteristics of Copper C101 (T2)

Exceptional Electrical Conductivity (≥101% IACS)

According to ASTM B193, Copper C101 delivers electrical conductivity of at least 101% International Annealed Copper Standard (IACS), making it one of the most conductive engineering materials. This allows efficient current transmission in high-frequency and high-load electrical systems.

Superior Thermal Conductivity (391 W/m·K)

Per ASTM E1952, the alloy has a thermal conductivity of approximately 391 W/m·K at room temperature, enabling effective heat dissipation in power electronics, transformers, and heat exchanger assemblies.

Excellent Ductility (≥35% Elongation)

With elongation values typically exceeding 35% (ASTM E8/E8M), Copper C101 demonstrates excellent ductility, which allows it to be cold-formed, bent, or deep drawn into intricate geometries without cracking.

High Workability and Cold Formability

C101 offers a cold workability rating of 90–95% compared to pure copper, making it suitable for machining, stamping, and forming operations in both soft and half-hard tempers. It retains dimensional stability even in thin-walled configurations.

Non-Magnetic and Non-Sparking

As a fully non-ferrous, non-magnetic, and non-sparking material, Copper C101 is ideal for applications in MRI equipment, explosion-proof components, and environments where magnetic interference must be minimized.

Stable Annealed State (Non-Heat Treatable)

This alloy is non-heat-treatable and is typically supplied in an annealed or cold-worked condition. Its strength (200–250 MPa tensile) is developed via mechanical deformation, ensuring thermal stability and ease of post-machining processes.

CNC Machining Challenges and Solutions for Copper C101 (T2)

Machining Challenges

• Material Gumming: High ductility causes chip adhesion and tool smearing.

• Tool Wear: High thermal conductivity increases heat transfer to tools, accelerating wear.

• Poor Chip Control: Produces long, stringy chips that tangle with tools and fixtures.

• Surface Marring: Prone to scratching during and post-machining.

Optimized Machining Strategies

Tool Selection

Copper C101 Cutting Parameters (ISO 513 Compliance)

Typical Machining Services for Copper C101 (T2)

Surface Treatment for Copper C101 CNC Parts

• Electroplating: Typically involves tin (3–5 µm), silver (2–10 µm), or nickel (5–25 µm) plating. It enhances corrosion resistance, provides solderability, and maintains electrical performance for connectors and terminals.

• Polishing: Use mechanical or electrolytic polishing to achieve surface roughness of Ra 0.2–0.8 µm. Improves aesthetics, electrical contact quality, and hygienic performance in medical or food-grade environments.

• Brushing: Produces satin or matte textures in a controlled grain direction. Typically used to reduce reflectivity and enhance the cosmetic appearance of architectural or consumer products.

• PVD Coating: Deposits hard coatings (2–5 µm) such as TiN or CrN, increasing surface hardness (up to 2000 HV) and wear resistance without compromising fine tolerances.

• Passivation: Removes surface oxides and contaminants to prepare parts for further treatment. Improves adhesion of coatings and long-term surface stability.

• Powder Coating: Provides a thick polymer layer (60–100 µm), improving resistance to moisture, abrasion, and UV degradation. Ideal for housing, control boxes, and outdoor components.

• Teflon Coating: Adds non-stick properties and chemical resistance with PTFE films ranging 10–50 µm. Common in flow systems and chemical processing equipment.

• Chrome Plating: Functional chrome (10–100 µm) boosts surface hardness (700–1000 HV) and wear resistance and adds a mirror-like finish. Used in electrical contacts and sliding assemblies.

Industry Applications of Copper C101 (T2)

• Electrical & Power Distribution: Bus bars, terminal lugs, electrical contacts, transformer components.

• Aerospace & Defense: EMI shielding, high-frequency signal paths, thermal management plates.

• Medical Devices: Imaging equipment, grounding systems, non-magnetic instruments.

• Automotive: Battery terminals, fuse boxes, high-current wiring systems.

• Consumer Electronics: Speaker terminals, antenna components, PCB grounding plates.

FAQs

• What machining tolerances can be guaranteed for custom Copper C101 components?

• Which CNC machining method is best for producing high-volume copper contact terminals?

• What surface finishes are recommended for electrical-grade Copper C101 parts?

• Are multi-axis or EDM services necessary for my complex copper geometry?

• How does Copper C101 perform in corrosion-prone environments after coating?