Product Specification

0.7mm 302 Stainless Steel Spring Wire with Soap-Coated Surface

Product Introduction

0.7mm 302 Stainless Steel Spring Wire is a cold-worked austenitic stainless steel wire designed for spring manufacturing and precision wire forming. It is made from AISI 302 stainless steel and supplied in a hard spring temper with a soap-coated surface.

The 0.7mm diameter is suitable for small and medium-sized springs where controlled wire dimensions, high tensile strength and repeatable forming behavior are required. Typical applications include compression springs, extension springs, torsion springs and other formed wire components.

AISI 302 stainless steel is an 18Cr-8Ni austenitic stainless steel grade commonly used for spring wire. During cold drawing, work hardening increases the tensile strength of the wire, making the material suitable for spring applications where elastic performance is required.

The soap-coated surface is commonly used for stainless steel spring wire and can provide lubrication during subsequent wire forming or spring coiling operations. Surface treatment should be selected according to the customer's coiling equipment, forming process and final application.

Product Specifications

*Mechanical properties should be confirmed against the applicable production standard and agreed specification before ordering.

AISI 302 Stainless Steel for Spring Applications

AISI 302 is an austenitic chromium-nickel stainless steel commonly used in spring wire production. Its nominal alloy system is based on approximately 18% chromium and 8% nickel, while the actual chemical composition depends on the applicable material standard.

For spring manufacturing, the final mechanical properties are influenced not only by the stainless steel grade but also by wire diameter, cold drawing reduction, temper condition and applicable standard.

This is why spring wire should be selected according to the required tensile strength, wire diameter, spring design and forming process rather than by grade alone.

Why Use Soap-Coated Spring Wire?

Soap coating is a surface treatment commonly used on stainless steel spring wire.

For automated spring coiling and wire forming, surface condition can affect friction between the wire and forming equipment. A suitable soap-coated surface can provide lubrication during forming and help support smoother wire feeding.

The actual suitability of the coating depends on:

• Spring coiling machine configuration

• Drawing and forming process

• Required surface cleanliness

• Lubricant compatibility

• Final spring application

• Subsequent cleaning or coating requirements

For applications requiring a specific surface condition, the coating type and processing requirements should be confirmed before production.

Mechanical Properties for 0.7mm Spring Wire

For 302 stainless steel spring wire in the 0.65–1.00mm diameter range, JIS G4314-based data lists different tensile-strength classes depending on the specified wire condition.

For example, the WPB range for AISI 302/304 is approximately 1850–2100 N/mm² in this diameter range. Other production specifications may define different mechanical-property ranges.

Therefore, the required tensile strength should be specified together with the standard and temper condition when ordering 0.7mm spring wire.

Applications

Compression Springs

0.7mm 302 stainless steel spring wire can be used for compression springs requiring a compact wire diameter and high tensile strength.

Typical applications include:

• Small mechanical assemblies

• Electrical components

• Consumer equipment

• Precision mechanisms

• General industrial components

Extension Springs

The wire can also be formed into extension springs where the spring is subjected to tensile loading.

The final suitability depends on spring geometry, working load, number of cycles and operating environment.

Torsion Springs

For torsion springs, wire diameter, coil diameter, leg configuration and working angle should be considered together.

0.7mm wire can be specified for relatively small torsion spring designs where the material and mechanical properties meet the required working conditions.

Precision Wire Forms

Beyond conventional springs, 302 stainless steel spring wire can be formed into clips, hooks and other elastic wire components.

The forming process should be evaluated according to the required geometry and the hardness of the supplied wire.

Product Advantages

AISI 302 Stainless Steel Grade

AISI 302 provides a commonly used stainless steel grade for spring wire applications. Its chromium-nickel composition provides the corrosion resistance associated with austenitic stainless steel.

0.7mm Diameter

The 0.7mm diameter provides a defined wire size for spring and wire-forming applications where dimensional control is important.

High Tensile Strength

The hard spring temper provides a high tensile-strength level suitable for spring manufacturing. For the specific 0.7mm product, the applicable tensile-strength range should be confirmed according to the selected standard and production specification.

Soap-Coated Surface

The soap-coated surface is suitable for wire feeding and spring coiling processes where additional surface lubrication is required.

Multiple International Standards

The product can be specified according to applicable ASTM, EN, DIN, JIS or GB requirements. The exact standard should be agreed before production to ensure that chemical composition, dimensions and mechanical properties are evaluated against the same specification.

Quality Control and EEAT Information

For spring wire, product quality should be evaluated through measurable parameters rather than appearance alone.

TOPONE can provide technical documentation and inspection information according to the order specification, including:

• Material grade verification

• Diameter and dimensional inspection

• Tensile strength testing

• Surface condition inspection

• Coil weight verification

• Packaging inspection

• Mill Test Certificate (MTC), when required

For production orders, customers should provide the required material standard, diameter tolerance, tensile-strength range, surface condition and packaging specification.

This information allows the spring wire to be evaluated against defined technical requirements rather than general product descriptions.

Ordering Information

When requesting a quotation for 0.7mm 302 stainless steel spring wire, it is recommended to specify:

1. Stainless steel grade: AISI 302

2. Wire diameter: 0.70mm

3. Surface: Soap-coated

4. Temper: Hard / spring temper

5. Required standard: ASTM, EN, DIN, JIS or GB

6. Tensile-strength requirement

7. Coil or spool requirements

8. Required coil weight

9. Quantity

10. Application or spring type

For customized spring wire requirements, providing the target spring design, working load and forming process can help determine the appropriate mechanical-property specification.

FAQ

What is 0.7mm 302 stainless steel spring wire used for?

It is commonly used for compression springs, extension springs, torsion springs and formed wire components where a 0.7mm wire diameter and high-strength spring temper are required.

What is the surface of this 302 spring wire?

This product uses a soap-coated surface. The coating is commonly used on stainless steel spring wire for wire drawing, feeding and spring coiling processes.

Is 302 stainless steel suitable for spring manufacturing?

Yes. AISI 302 is a commonly used austenitic stainless steel grade for spring wire. Its work-hardening behavior allows high tensile strength to be obtained through cold working.

What tensile strength is available for 0.7mm 302 spring wire?

The product page specifies 1850–2150 N/mm². However, the final tensile-strength requirement should be confirmed against the applicable standard, wire condition and purchase specification.

Can the wire be supplied with different surface finishes?

Yes. Depending on the product specification, stainless steel spring wire can be supplied with soap-coated or bright surface conditions.

What information should be provided for a spring wire quotation?

The most important information includes grade, diameter, surface condition, tensile strength, applicable standard, quantity, coil weight and intended application.

Technical Selection Guide

For spring manufacturers, selecting 302 stainless steel spring wire should begin with the actual spring design rather than simply choosing a wire diameter.

Consider the following parameters:

Wire diameter → spring diameter → working load → deflection → operating cycles → temperature → corrosion environment → forming method

For example, a 0.7mm wire may be appropriate for a compact spring, but the final selection also depends on the required spring rate, working stress and fatigue conditions.

For demanding applications, TOPONE recommends confirming the spring design and mechanical-property requirements before mass production.

Related Stainless Steel Spring Wire Options

TOPONE also supplies stainless steel spring wire in different grades, diameters and surface conditions, including 302, 304 and 316 grades.

Available configurations may include:

• 302 stainless steel spring wire

• 304 stainless steel spring wire

• 316 stainless steel spring wire

• Bright surface spring wire

• Soap-coated spring wire

• Different wire diameters and tensile-strength ranges

• Coil and spool packaging

The appropriate grade and surface should be selected according to the required corrosion environment, mechanical properties and forming process.