Alternative spring materials

Alloy 25 by Materion offers the highest strength (> 1500 MPa) among all copper-based alloys. Its electrical conductivity is significantly higher than that of other high-strength copper alloys. Compared to other alloys, Alloy 25 (UNS C17200), Alloy M25 (C17300) and Alloy 165 (C17000) have both a very high strength and a high conductivity. Thus, they are particularly suitable for highly stressed electrical contacts and components.

 

• Very good properties for coating in order to reduce the contact resistance
• Good R/T ratio, for bending and embossing, strength dependent
• Weldable with special equipment
• Can be used up to 250 °C without creepage
• Good corrosion resistance, can also be used without coating
• Non-magnetic

Springs manufactured from beryllium copper are employed across a broad spectrum of applications, including high-frequency (RF) engineering, measurement and control technology, nuclear physics, aerospace, and the entire field of electronic data processing. Due to their excellent mechanical and electrical properties, they are particularly well suited for high-load electrical contacts and precision components.

 

ZILLKON Contact springs

Physical Properties of Copper Beryllium
CuBe2 C17200 2.1247

Cu Ni 2 Be can achieve a conductivity above 45 % IACS and a strength up to 970 MPa (UTS). This combination of properties makes these alloys particularly suitable for applications such as heat dissipation modules, resistance welding components and other electrical fields of application.

• Good R/T ratio, for bending and embossing, strength dependent
• Good corrosion resistance, can also be used without coating
• Weldability unknown
• Can be used up to 260 °C without creepage
• Very good properties for coating in order to reduce the contact resistance
• non-magnetic

The copper-nickel-beryllium alloy is widely utilized in technical fields such as electronics, aerospace engineering, marine applications, and automotive technology due to its excellent mechanical strength, corrosion resistance, and reliable electrical conductivity.

Physical Properties of
Copper-nickel-beryllium 
CuNi2Be C17510

The bronze alloy CuSn6 is one of the most used types of bronze. It is applied for connectors, contact pins as well as stamped bending parts and springs requiring good electrical conductivity.

Physical Properties of Copper-bronze CuSn6
DIN 1654

CuSn8 (C5210HP) is a copper-tin alloy characterized by high strength, good corrosion resistance, and excellent sliding properties. It offers good wear resistance and high mechanical load capacity, making it particularly resistant to friction and wear.


 

• Very good properties for coating in order to reduce the contact resistance
• Higher R/T ratio, for bending and embossing, strength dependent
• Weldable
• Good corrosion resistance, can also be used without coating
• Non-magnetic

At 150 °C and 100 h the strain relaxation resistance decreases by 15 %.

 

Thanks to its excellent properties, CuSn8 is widely used in demanding applications such as bearing bushings, spring contact materials, and electrical components. It is particularly employed in the automotive and mechanical engineering industries for parts that must withstand high mechanical loads and exhibit superior wear resistance.

Physical Properties of
Hyper phosphor bronze 
CuSn8 C5210HP

CuSn10-C is a construction material showing high strain with medium hardness. CuSn10-C is both resistant to wear and corrosion, in particular to seawater and mine waste water.

 

• Very good properties for coating in order to reduce the contact resistance
• Resistant to stress corrosion cracking
• Medium R/T ratio, for bending and embossing
• Weldable
• Good corrosion resistance, can also be used without coating
• Non-mahnetic

At 150°C and 100h the strain relaxtion resistance decreases by 15%. Within the group of bronzes, CuSn10 is the material with the highest strength.

 

It is well suited for use in connectors, contact springs, relay springs, and leaf springs.

Physical Properties of
Hyper-copper-bronze CuSn10
C5240HP

Titanium iron copper is an alloy combining the advantages of the three metals. Titanium gives the alloy a high strength with low weight as well as an excellent resistance to corrosion. Iron contributes to hardness and stability while copper ensures good electrical and thermal conductivity.
This combination makes the alloy resistant to high temperatures and aggressive environments. 

 

• Excellent corrosion resistance, can also be used without coating
• Very good R/T ratio, for bending and embossing
• Weldable
• Very good properties for coating in order to reduce the contact resistance
• Non magnetic

At 150 °C and 1000 h the strain relaxation resistance only decreases by 2 %.

It is often used in aerospace, medical engineering and in electronic components where high strength and corrosion protection is required. It is also applied in the chemical industry as well as in offshore construction projects. Thanks to its electrical and thermal properties titanium iron copper is also suitable for special electrical contacts and heat exchangers.

Physical Properties of Titanium-iron-cooper
NKT322 C19910

CuNi3SiMg is offered with high strength values which lead to an increased R/T ratio. The alloy has a good relaxation resistance and electrical conductivity.

 

• Good corrosion resistance, can also be used without coating
• Good R/T ratio, for bending and embossing, strength dependent
• Very good properties for coating in order to reduce the contact resistance
• Weldable
• Non-magnetic

Only at 120 °C and 1000 h the strain relaxation resistance decreases by 5 %. 

This combination of high strength and reliable electrical performance makes CuNi3SiMg ideal for applications that demand both high mechanical strength and excellent electrical properties, such as those found in the automotive and electronics industries. The alloy is particularly well-suited for small connectors requiring high spring forces and for applications exposed to elevated operating temperatures.

Physical Properties of
K55
CuNi3SiMg
C70250

CuCrSiTi is easily formable. Its mechanical strength is similar to that of a standard bronze. The advantages are the high electrical conductivity and an outstanding thermal resistance.

 

• Very good properties for coating in order to reduce the contact resistance
• Good R/T ratio, for bending and embossing
• Weldable
• Good corrosion resistance, can also be used without coating
• Non magnetic

At 120 °C and 1000 h the strain relaxation resistance decreases by approx. 15 %. 

K75 is used in medical technology, the electrical industry, the automotive sector, and mechanical engineering due to its high strength, elasticity, and fatigue resistance. Typical applications include precision springs, switching mechanisms, suspension components, and mechanical control systems that are subject to high loads and repeated stress.

 

Physical Properties of 
K75 
CuCrSiTi C18070

Inconel 718 is a nickel-based heat resistant alloy. This hardenable nickel chrome alloy stands out for its good wear resistance, tensile strength, high-temperature strength and breaking strength at low temperatures and up to 700 °C.

 

• Good R/T ratio, for bending and embossing, strength dependent
• Good corrosion resistance, can also be used without coating
• Weldability unknown
• Can be used up to 760 °C without creepage
• Very good properties for coating in order to reduce the contact resistance
• Non magnetic

This material is ideal for many high-temperature applications as well as low-temperatures applications, such as EMC shields.

Physical Properties of
Inconel 718

The material 1.4310 is an austenitic chrome-nickel steel that convinces with its excellent formability. This stainless steel belongs to the V2A steel group and is often used as spring steel as it is particularly predestined for the production of technical springs. Thanks to the alloy with 17 % of chrome and 7 % of nickel it has a high resistance to corrosion. Its high strength is achieved by cold rolling; values above 2000 N/mm² are possible; unfortunately magnetism increases then. The material is ideal for stainless springs requiring increased strength and temperature with low electrical conductivity. 

 

• Good corrosion resistance, can also be used without coating
• Good R/T ratio with medium hardness, for bending and embossing
• Weldable
• Good properties for coating in order to reduce the contact resistance
• Non magnetic

Stainless steel 1.4310 is widely used in electrical and communication technology due to its good electrical conductivity and mechanical properties, for example in EMI shielding, gaskets, and cable shielding. In addition, the material is used in the automotive industry, mechanical engineering, food processing, and the pharmaceutical industry, where corrosion resistance, chemical resistance, and high hygiene standards are particularly critical.

Physical Properties of
Stainless steel 1.4310