CONTACT MATERIAL:
BERYLLIUM COPPER ALLOY 172 (UNS C17200) per ASTM B 194
Properties of BERYLLIUM COPPER:
Chemical composition: Cu 98.1%, Be 1.9%
Hardness: 36-43 Rockwell C
Density: .298 lbs/in3
Electrical Conductivity: 22% IACS*
Resistance: 10 mΩ Max
Operating Temperature: -55°C/+125°C
Melting point: 980°C/865°C (liquidus/solidus)
Stress Relaxation : 96% of stress remains after 1,000 hours @ 100 °C; 70% of stress remains after 1,000 hours @ 200 °C
*International Annealed Copper Standard, i.e. as a % of pure copper.
Since BeCu loses its spring properties over time at high temperatures; it is rated for continuous use up to 150°C. For applications up to
300°C, Mill-Max offers other materials. Contact Tech Support for more info.
†
†
LOOSE PIN/RECEPTACLE USED:
3435 (Brass Alloy)
BRASS ALLOY 360 per ASTM B 16, or 385 per ASTM B455
Properties of BRASS ALLOY 360 ASTM B 16:
Chemical composition: Cu 63% (max), Pb 3.7% (max)†, Fe .35% (max), Zn remainder
Temper as machined: H02/H04
Yield Strength: 25-45 ksi
Tensile strength: 57-80 ksi
Hardness as machined: 80-90 Rockwell B
Electrical conductivity: 26% IACS*
Melting point: 1000°C/840°C (liquidus/solidus)
Properties of BRASS ALLOY 385 ASTM B 455:
Chemical composition: Cu 60% (max), Pb 3.5% (max)†, Fe .35% (max), Zn remainder
Temper as machined: H02/H04
Yield Strength: 16 ksi(min)
Tensile strength: 48 ksi(min)
Hardness as machined: 80-90 Rockwell B
Electrical conductivity: 28% IACS*
Melting point: 1000°C/840°C (liquidus/solidus)
After machining, brass parts are often annealed (softened) for subsequent bending, swaging or crimping. A partial anneal down to 60±10 RB
is recommended for 90° bends, a full anneal down to 35±15 RB is recommended for pins or terminals that are swaged (riveted) to a circuit
board or crimped to a wire.
Note: Plated Brass parts need a barrier plate to prevent zinc diffusion, 50μ” min. nickel or 100μ” min. copper is recommended by ASTM B
545 and 579. ASTM B 488 also recommends a 50μ” min. nickel barrier plate beneath gold to prevent copper diffusion inherent with all
copper alloy products.
†RoHS-2 directive 2011/65/EU, exemption 6c allows up to 4% lead as an alloy agent in copper.
*International Annealed Copper Standard, i.e. as a % of pure copper.
INSULATOR MATERIAL:
PCT Polyester (Injection Molded)
Properties: