Electrical Contacts

Electrical Contacts

Electrical_Contacts

The contact parts are important components in switching devices. They have to maintain their function from the new assembled state until the end of the functional life of the devices.

Common materials currently used in the Industry

Brass Phosphor-bronze Beryllium copper
Brass contacts offer cost benefits, good conductivity and dependable electrical and mechanical performance for simple low voltage and low current applications.

Phos-bronze contacts, on the other hand, generally perform well in extended high-temperature environments.

Phos-bronze is typically the material of choice for contacts used in moderate-power connectors.

Compared to brass and phosphor-bronze, Beryllium Copper has superior strength and spring properties and therefore comes in the smallest size and lightest weight.

Not surprisingly, Beryllium Copper is the contact material of choice for most telecom, military and aerospace applications. For smaller contacts, Beryllium Copper is the material of choice as it helps miniaturisation.

Desired Properties from Materials for Electrical Contacts

  • Good Electrical and thermal conductivity
  • Good Strength
  • Good Spring Properties
  • High arc erosion resistance
  • High resistance against welding
  • Low contact resistance
  • Good arc moving properties
  • Good arc extinguishing capability
  • High hardness
  • High corrosion resistance
  • Good mechanical workability
  • Environmentally friendly materials

Copper Titanium Alloy

  • Copper Titanium alloys are beryllium free alloys, provide much better performance as compared to other alloys.

  • Copper Titanium alloys have high strength and excellent spring properties over extended cycles.

  • Copper Beryllium and Copper Titanium soften at much higher temperature without losing its conductivity drastically and therefore longevity in performance.

Specification of Materials for Electrical Applications

Composition Tensile Strength (MPa) Annealing Temperature C Conductivity IACS Hardness
Stainless Steel

12-20% Cr

14-18% Ni

700 MPa 250 C 7%-8% 420
Spring Brass

70% Copper

30% Zinc

500 MPa 180 C 50%-80% 120
Phosphorus Bronze

95% Copper

4.5% Tungsten

Some Zinc

650 MPa 200 C 15% 202
Copper Beryllium 2% Beryllium 1200 MPa 400 C 11%-25% 340
Copper Titanium Proprietary info 1240 MPa 450 C 11%-25% 400

Applications of Copper Titanium in Electrical Contacts

  • Electrical connectors
  • MIL Standard Connectors Pins
  • Phone Battery Contacts
  • EMI Shielding Gaskets
  • Touch Pad Springs
  • Lugs
  • Low Voltage Switchgear
  • High Voltage Canted Springs
  • Electrical Switch and Relay Blades
  • Fuse Clips
  • Spring Connectors
  • Contact Bridges
  • Belleville Washers
  • Navigational Instruments