Designation and Standards

• Standard Designation: BZn18-18 (Zinc-Copper-Nickel Alloy)

• Applicable Standard: GB/T 5231-2012 (Wrought Copper and Copper Alloys)

• International Equivalent Grades: ASTM C75200 (American Standard), JIS C7521 (Japanese Standard)

• Material Category: Copper-Nickel-Zinc Alloy (Cu-Ni-Zn), Copper Content 62.0%-66.5%, Nickel + Cobalt 13.5%-19.5%, and the remainder being zinc.

Product Features

High Strength and Corrosion Resistance

Tensile Strength: ≥440 MPa

Hardness Range: HB120-210

Corrosion Resistance: Excellent against seawater and mild acids, with a corrosion rate of ≤0.01 mm/a

Excellent Conductivity and Electromagnetic Shielding

Electrical Conductivity: ≥6% IACS

Thermal Conductivity: 33 W/(m·K)

Suitable for high-precision electronic components and electromagnetic shielding parts

Processing Performance

Good cold and hot workability, supporting rolling, stretching, and other processes

Poor machinability and weldability

Surface Characteristics

Silver-white appearance, supports electroplating and passivation treatments

Ideal for precision instruments and decorative applications

Chemical Composition

Physical Properties

Mechanical Properties

Heat Treatment Specifications

Casting Temperature: 1170°C

Hot Rolling Temperature: 950-970°C

Annealing Process:

Conventional Annealing: 700-750°C

Stress Relief Annealing: 250°C

Age Hardening:

After quenching, age at 400-450°C for 5-20 hours to achieve hardness up to HV450

Core Application Fields

• Electronics Industry:

Connectors and Terminals: High conductivity and corrosion resistance for 5G communication devices.

Relays and Switches: High elasticity and fatigue resistance.

• Precision Machinery:

Optical Instrument Components: Watch gears and lens mounts requiring high dimensional stability.

• Marine and Chemical Industry:

Corrosion-resistant Valves: Suitable for seawater desalination systems with chloride ion resistance.

• Daily Goods:

Decorative Hardware: Tableware and eyeglass frames requiring excellent surface finish and aesthetics.

Processing Precautions

• Cold Processing Limitations: During cold heading or stamping, deformation should be controlled within 20% to prevent cracking.

• Welding Process: Prefer laser welding or electron beam welding to minimize porosity defects.

• Surface Treatment: Before nickel or gold plating, apply a base layer (such as a 3μm nickel layer) to ensure adhesion.

• Environmental Compliance: Low lead content (≤0.02%), but waste materials should be handled as hazardous waste.

Reference Standards

• Chemical Composition and Processing Norms: GB/T 5231-2012, ASTM B122 (American Standard for Plates)

• International Standards: JIS H3130 (Japanese Standard), ISO 426-2 (International Standard)

Note: The above data is consolidated from multiple industrial standards and technical documents. Actual performance may vary depending on manufacturing processes, and the specific results should be based on the supplier's test report.