0.4mm AISI 304 Soap-Coated Stainless Steel Wire for Spring Making

Product Specification

0.4mm 304 Stainless Steel Spring Wire

TOPONE 0.4mm 304 Stainless Steel Spring Wire is a cold-drawn stainless steel wire designed for precision spring manufacturing and wire forming applications. It is manufactured from AISI 304 / SUS304 stainless steel and supplied with a soap-coated surface for applications requiring a lubricated wire surface during forming.

With a nominal diameter of 0.4 mm, this spring wire is suitable for small-diameter compression, extension and torsion springs, as well as selected wire-forming components. For spring wire in the 0.23–0.40 mm diameter range, the listed WPB tensile strength is 2050–2300 N/mm².

Material grade, wire diameter, tensile strength, surface condition and forming process should be considered together when selecting stainless steel spring wire for a specific application.

Product Specifications

Note: Tensile strength should be confirmed according to the applicable standard, wire diameter and agreed product specification before production.

304 Stainless Steel Material

AISI 304 is an austenitic stainless steel grade commonly used for stainless steel wire and spring applications. The material contains chromium and nickel, which contribute to its corrosion-resistant characteristics.

For spring wire, the material grade is only one part of the selection process. The final mechanical condition is also related to wire diameter, cold drawing and specified tensile strength.

For 0.4mm spring wire, buyers should confirm:

• AISI 304 / SUS304 material grade

• 0.4 mm nominal diameter

• Diameter tolerance

• Required tensile strength

• WPB or other applicable spring-wire class

• Soap-coated or bright surface

• Spring forming method

• Applicable standard

• Operating environment

Cold-Drawn Manufacturing

The wire is produced through cold drawing to achieve the required diameter and mechanical condition. For fine spring wire such as 0.4 mm, dimensional control and surface condition are important considerations during production and subsequent forming.

The final specification should be defined according to the spring design, forming equipment and applicable standard.

Soap-Coated Surface

The soap-coated surface provides a lubricated finish that can be used for certain spring forming and cold-forming processes.

For customers using automatic spring coiling or forming equipment, the surface condition should be selected according to the equipment, forming speed, lubrication requirements and downstream processing conditions.

If a bright surface is required instead, the surface specification should be confirmed before production.

Applications

Compression Springs

0.4mm 304 stainless steel spring wire can be used for small-diameter compression springs in mechanical and industrial components.

Extension Springs

The wire is also suitable for selected extension spring applications where the required diameter and mechanical properties match the spring design.

Torsion Springs

For torsion springs, wire diameter, tensile strength, spring index, forming process and working conditions should be evaluated together.

Precision Wire Forms

The wire can also be used for small formed-wire components such as hooks, clips and retaining parts, subject to the required forming process.

Typical Application Areas

• Small mechanical springs

• Industrial hardware

• Electrical components

• Mechanical assemblies

• Precision wire forming

• Fishing equipment components

• Small retaining components

Product Advantages

1. 0.4mm Fine Wire Diameter

The 0.4mm diameter is suitable for spring designs requiring a relatively small wire section. Final spring performance depends on the complete spring design rather than wire diameter alone.

2. AISI 304 Stainless Steel

AISI 304 provides a commonly used stainless steel option for spring and wire-forming applications where corrosion resistance is required.

3. WPB Spring Wire Condition

For the 0.23–0.40 mm diameter range, the listed WPB tensile strength is 2050–2300 N/mm². The applicable strength class should be confirmed against the customer's required standard and specification.

4. Soap-Coated Surface

The soap-coated surface provides lubrication for suitable forming processes and can be selected according to spring manufacturing requirements.

5. Multiple Applicable Standards

The product can be specified according to ASTM, JIS, EN, DIN or GB requirements, subject to the agreed technical specification.

How to Select 0.4mm Stainless Steel Spring Wire

Before purchasing 0.4mm 304 stainless steel spring wire, buyers should confirm the following technical requirements.

Material Grade

Confirm whether AISI 304 / SUS304 is required for the application.

Wire Diameter

Specify 0.4 mm nominal diameter together with the required diameter tolerance.

Tensile Strength

Confirm the required tensile strength and applicable spring-wire class. For the 0.23–0.40 mm range, the listed WPB tensile strength is 2050–2300 N/mm².

Surface Finish

Choose soap-coated or another required surface condition according to the spring-forming process.

Spring Type

Confirm whether the wire will be used for compression, extension or torsion springs.

Operating Conditions

Consider temperature, moisture, exposure to chemicals and other environmental conditions when selecting the stainless steel grade and spring specification.

Quality Inspection

Quality inspection for 0.4mm stainless steel spring wire should focus on measurable technical characteristics.

Depending on the agreed specification, inspection can include:

• Chemical composition

• Wire diameter and tolerance

• Tensile strength

• Surface condition

• Visual inspection

• Coil dimensions

• Weight

• Packaging condition

• Applicable standard requirements

Inspection requirements should be confirmed according to the customer's technical specification and purchase order.

Packaging

The 0.4mm stainless steel spring wire can be supplied in coils, spools or palletized packages according to wire weight, handling requirements and customer specifications.

For export orders, packaging can be selected according to transportation conditions and downstream production requirements.

FAQ

What material is the 0.4mm spring wire made from?

The wire is manufactured from AISI 304 / SUS304 stainless steel.

What is the diameter of this spring wire?

The nominal wire diameter is 0.4 mm.

What is the tensile strength of the 0.4mm 304 spring wire?

For the 0.23–0.40 mm diameter range, the listed WPB tensile strength is 2050–2300 N/mm². The final specification should be confirmed according to the applicable standard and order requirements.

What is the surface of this spring wire?

This product has a soap-coated surface designed for suitable spring-forming and cold-forming applications.

What types of springs can be made from 0.4mm wire?

The wire can be used for selected compression, extension and torsion spring applications, depending on the spring design and required mechanical properties.

What standards are available?

The product can be specified according to ASTM, JIS, EN, DIN or GB requirements, subject to the agreed product specification.

Can the surface or mechanical properties be customized?

Surface condition, tensile strength, diameter tolerance and packaging can be discussed according to the customer's technical requirements.