Introduction

• C19400 (CuFe2P / CW107C) copper-iron alloy, also known as iron bronze, has a microstructure primarily composed of α-Cu and Fe. This alloy combines the excellent electrical conductivity of copper with the enhanced strength of iron, while the addition of phosphorus improves its corrosion resistance and machinability. It possesses good thermal and electrical properties, with a conductivity of up to 60% IACS. It is commonly used in applications requiring high strength and corrosion resistance. The most typical application is for lead frames in integrated circuits or separator components. Additionally, C19400 can be manufactured as fully etched or partially etched materials.
• Strength: The CuFe₂P alloy exhibits high tensile strength. The addition of iron significantly enhances its strength and hardness compared to pure copper alloys. With moderate strength, this alloy is widely used in environments requiring durability.
• Hardness: The inclusion of iron increases the alloy’s hardness, making it suitable for components that endure higher loads.
• Toughness and Ductility: Compared to other high-strength alloys, CuFe₂P retains a certain degree of ductility and toughness, allowing it to withstand some deformation.
• Electrical Conductivity: Although the electrical conductivity of CuFe₂P is lower than pure copper, it still offers good conductivity (60% IACS). This makes it suitable for electrical and electronic applications requiring a balance between strength and conductivity.
• Excellent Corrosion Resistance: The addition of phosphorus significantly improves the alloy’s resistance to corrosion in humid, acidic, or alkaline environments. It effectively prevents oxidation and corrosion in harsh conditions.
• Wear Resistance: The presence of iron and phosphorus in the alloy contributes to its enhanced wear resistance, making it especially suitable for friction components.
• Weldability: Due to the phosphorus content, the alloy has good weldability, though excessive heat should be avoided to prevent phosphorus evaporation or brittleness. It also has excellent hot-dip tin plating properties, making it ideal for soft soldering and gas-shielded welding.

Chemical Composition

• Fe: 2.1%~2.6%
• Zn: 0.05%~0.2%
• P: 0.015%~0.15%
• Cu: Remainder

Alloy Standard

• ASTM: C19400——ASTM B465
• DIN: CuFe2P/2.1310
• EN: CuFe2P/CW107C
• JIS: C1940

Physical Properties

• Density: 8.91 g/cm³
• Electrical conductivility: 64 IACS%(20°C)*(value for the lowest temper class)
• Modulus of elasticity: 121 GPa
• Coefficient of thermal expansion: 16.3 10^-6/K
• Thermal conductivity: 260 W/(m*K)

Mechanical Properties

Application

• Electrical and Electronics Industry: CuFe₂P alloy is widely used in electrical connectors, circuit breaker components, contact springs, electrical clamps, wires, and cables due to its excellent electrical conductivity, mechanical properties, and corrosion resistance.
• Automotive Industry: As connectors and conductive components in automotive electrical systems, CuFe₂P alloy is applied in automotive electronics thanks to its high strength and corrosion resistance.
• High-Strength, Wear-Resistant Components: Due to its excellent wear resistance, CuFe₂P alloy is extensively used in applications requiring friction-resistant components, such as mechanical gears, bearings, and sliders.
• Aerospace Industry: The alloy’s high-temperature resistance and corrosion resistance make it suitable for use in demanding aerospace components.
• Lead Frames: Copper alloys for lead frames are generally categorized into copper-iron, copper-nickel-silicon, copper-chromium, and copper-nickel-tin systems (e.g., JK-2 alloy). Multi-component alloys, such as ternary and quaternary systems, often achieve better performance and lower costs compared to traditional binary alloys. Among these, copper-iron alloys are the most prevalent, with C19400 (CuFe₂P) being a representative grade, known for its excellent mechanical strength, stress relaxation resistance, and low creep properties. This makes it an ideal material for lead frames. Due to the requirements of lead frame fabrication and packaging applications, materials must possess not only high strength and thermal conductivity but also good solderability, processability, etching properties, and oxidation film adhesion. Materials are evolving towards high strength, high conductivity, and low cost. By adding trace amounts of multiple elements to copper, the strength and overall performance of the alloy can be improved without significantly reducing conductivity (ensuring lead frames remain deformation-resistant). Current development focuses on materials with tensile strength exceeding 600 MPa and electrical conductivity above 80% IACS. Copper strips are also advancing towards higher surface quality, precise flatness, and uniform properties. Thickness is gradually decreasing, from 0.25 mm to 0.15 mm and 0.1 mm, with ultra-thin variations of 0.07–0.1 mm and specialized shapes becoming more common.