Steel Wire Bars

Straightened Spring Steel Wires for Prototyping, Wire Forms and Custom Applications

Straightened spring steels are pre-cut lengths of spring steel wire that have been processed to achieve a high degree of straightness. They are suitable for prototyping, development, repairs and the production of custom wire forms, spring arms, retaining elements and simple spring components.

The standard rods are 1,000 mm long and are available in different wire diameters, tensile strengths and materials. Unlike soft round steel, spring steel wire is already supplied in a high-strength condition. It therefore cannot be bent or machined without limitations. The bending radius, forming method and springback must suit the wire diameter and material.

Meaning of the Specifications in the Product Table

Tensile strength depends on both the material and the wire diameter. When replacing an existing wire, the diameter, material and Rm value must therefore be compared together.

Selecting the Material

Spring Steel 1.1200

1.1200 is a high-strength, unalloyed spring steel for many technical applications in dry or suitably protected environments. It provides high strength and good spring properties but is not permanently corrosion-resistant without a coating or suitable protection.

Stainless Spring Steel 1.4310

1.4310 is a stainless spring steel with good elastic properties and increased corrosion resistance. It is suitable for many applications involving humidity or regular cleaning. Due to heavy cold working, the material may become slightly magnetic.

Stainless Spring Steels 1.4568 and 1.4571

These materials are used where additional requirements apply regarding strength, temperature or corrosion resistance. Suitability must be assessed according to the surrounding media, operating temperature, loading and required service life. Stainless spring steels are not resistant to every chemical environment.

Bending and Forming Recommendations

Straightened spring steel has a high strength and shows significant springback during bending. After unloading, the resulting angle will therefore be smaller than the angle produced during forming.

For reliable processing:

• use suitable bending tools,

• avoid sharp bends and notches,

• provide sufficiently large bending radii,

• guide the wire and tool securely,

• test sample parts before series production.

Very tight radii, repeated bending in opposite directions or damage caused by pliers may produce cracks. Straightening, bending and cutting may also affect the original straightness and create local residual stresses.

Cutting, Drilling and Grinding

Tools suitable for high-strength spring steel wire are required for cutting. Side cutters intended for soft wire may be damaged. Wire ends may spring away during cutting, so safety glasses and suitable gloves should be worn.

Drilling, milling and turning are only possible to a limited extent because of the high strength and require suitable tools and machining parameters. Sharp cut edges and burrs should be removed without unnecessarily weakening the cross-section.

Welding or local heating may change the microstructure, strength and corrosion behaviour and should only be carried out after technical assessment.

Heat Treatment After Forming

After forming, heat treatment may be used to reduce processing stresses or establish the intended properties of certain materials. Temperature, duration and cooling method must suit the material and supplied condition.

Febrotec specifies the following guide values:

• 1.1200: 280°C for 0.5 hours, followed by air cooling,

• 1.4310: 380°C for 0.5 hours, followed by air cooling,

• 1.4568 or 1.4571: 450°C for 1 hour, followed by air cooling.

Heat treatment may affect dimensional accuracy, surface condition and straightness. Functional or safety-relevant components require technical verification.

Typical Applications

Straightened spring steels are suitable for wire forms, spring arms, retaining clips, safety wires, operating rods, shafts with spring action, prototypes and repair parts.

They are not automatically suitable as precision shafts, guide rods or load-bearing axles. Straightness, diameter tolerance, surface condition and load capacity must be assessed separately for these applications.

Frequently Asked Questions

Can straightened spring steel be bent by hand?

Small diameters may sometimes be formed by hand. Suitable bending tools are required for reproducible shapes and larger wire diameters.

Is the wire perfectly straight?

The wire has been straightened but remains subject to manufacturing tolerances. Suitability must be checked for precision guiding applications.

Can the wire be stress-relieved after bending?

In principle, yes, provided that the temperature and duration suit the material and supplied condition. The specified values are guidelines and do not replace testing of the finished component.

Which material is suitable for humid environments?

1.4310 and, depending on the requirements, 1.4568 or 1.4571 provide better corrosion resistance than 1.1200. The specific operating environment remains decisive.

Further standard and custom-made springs can be found in our spring elements overview.