Beryllium Copper

Beryllium copper is a high-performance mold alloy offering unmatched thermal conductivity, excellent strength, and superior surface quality for high-speed precision die casting.

Introduction to Beryllium Copper

Beryllium copper (BeCu) is a high-performance copper-based alloy combining exceptional thermal conductivity, strength, and wear resistance. As one of the most advanced mold materials available, BeCu is extensively used in die casting and plastic injection tooling to improve cycle time, cooling performance, and dimensional accuracy.

At Neway Die Casting, Beryllium Copper is applied to tooling components that require rapid heat dissipation, tight tolerances, and enhanced mold durability, especially in high-precision aluminum and zinc alloy castings.

Beryllium Copper Chemical Composition (Typical C17200 Grade)

Element	Weight %	Function
Copper (Cu)	~97.75	Base alloy, provides thermal/electrical conductivity
Beryllium (Be)	1.8–2.0	Increases strength, hardenability, and thermal resistance
Cobalt (Co), Nickel (Ni)	≤ 0.5	Enhances age-hardening response
Other (Fe, Si, etc.)	≤ 0.25	Impurity control for conductivity and strength balance

C17200 (Alloy 25) is the most common high-strength beryllium copper grade, conforming to ASTM B196 and RWMA Class 4 standards.

Physical Properties of Beryllium Copper

Property	Value & Unit
Density	8.26 g/cm³
Thermal Conductivity	105–130 W/m·K
Electrical Conductivity	20–30 % IACS
Coefficient of Thermal Expansion	17.5 µm/m·°C
Melting Range	870–980 °C
Specific Heat Capacity	~380 J/kg·K

Superior thermal conductivity enables BeCu molds to cool up to 5× faster than conventional steels, reducing cycle time significantly.

Mechanical Properties (Age-Hardened C17200)

Property	Value & Unit
Tensile Strength	1100–1400 MPa
Yield Strength	800–1200 MPa
Hardness	38–45 HRC
Elongation	2–8 %
Modulus of Elasticity	~128 GPa
Fatigue Strength	~310 MPa

These values allow BeCu to withstand both thermal and mechanical stresses in precision casting environments.

Die Casting Tooling Advantages

BeCu is the material of choice in tooling applications where rapid thermal extraction and anti-soldering properties are critical:

Rapid cooling reduces cycle times by 20–40%
Resists aluminum soldering and thermal fatigue in core pins and inserts
High polishability makes it ideal for thin-wall or optical-grade mold surfaces
Better dimensional repeatability due to lower thermal distortion

At Neway’s tool and die workshop, BeCu is commonly used in:

Core pins, sleeve inserts, and gate bushings
High-performance prototype tooling for aluminum die casting
Shut-off and sealing surfaces in complex cavity systems

Common Applications

Beryllium copper excels in scenarios demanding both conductivity and mechanical strength:

Thin-wall electronic enclosures requiring dimensional precision
High-speed mold cycles for zinc and aluminum components
Molds with asymmetric cooling paths or localized hotspots
Die inserts and cores in high-pressure low-volume production
Sliding shut-off blocks or rotating cores with wear exposure

Machining Challenges and Solutions

BeCu is harder than most copper alloys and generates fine particulate dust, which must be handled with care:

Requires rigid tool setups and sharp carbide cutters
Low-speed, high-feed machining preferred to avoid surface hardening
Dust must be collected via wet systems or HEPA filtration due to beryllium toxicity

Neway ensures safe and precise BeCu CNC machining using: