Every spring steel grade we produce and export, from Chinese 65Mn to Japanese SUP series and European 51CrV4 — with hardness windows, equivalent standards and direct links to full data sheets.
Spring Steel Grades We Supply
Every grade below is stocked or produced on mill lots with an EN 10204 3.1 certificate. Click any grade for its full chemical composition, mechanical properties, heat-treatment windows and equivalent standards.
| Grade | Standard / UNS | Typical Hardness | Key Character | Details |
|---|---|---|---|---|
| 65Mn Spring Steel | GB/T 1222 65Mn (AISI 1566) | 38 – 50 HRC | Classic Chinese Mn spring steel; low cost, versatile | View grade → |
| 6150 Spring Steel | SAE 6150 / UNS G61500 | 45 – 52 HRC | Chromium-vanadium; excellent fatigue life in coil and leaf springs | View grade → |
| 9260 Spring Steel | SAE 9260 / UNS G92600 | 50 – 55 HRC | Silicon-manganese; very high elastic limit for heavy-duty springs | View grade → |
| SUP9 Spring Steel | JIS G4801 SUP9 | 40 – 48 HRC | Japanese Mn-Cr spring steel for automotive leaf springs | View grade → |
| 50CrV4 / 51CrV4 Spring Steel | EN 10089 51CrV4 (1.8159) | 43 – 50 HRC | European Cr-V workhorse for valve and precision springs | View grade → |
| 5160 Spring Steel | SAE 5160 / UNS G51600 | 44 – 52 HRC | Chromium spring steel; the standard for automotive leaf springs | View grade → |
| 1095 Carbon Spring Steel | AISI 1095 / UNS G10950 | up to 60 HRC | 0.95% C high-carbon steel for blades, washers and flat springs | View grade → |
| 60Si2MnA / SUP7 Spring Steel | GB/T 1222 60Si2MnA (JIS SUP7) | 45 – 52 HRC | Higher silicon for elasticity; railway and heavy vehicle springs | View grade → |
| SUP12 / 9254 Spring Steel | JIS SUP12 / SAE 9254 | 48 – 55 HRC | Si-Cr valve spring steel; outstanding fatigue and sag resistance | View grade → |
| 301 / 302 Stainless Spring Steel | ASTM A666 Type 301 / 302 | 35 – 50 HRC | Stainless spring strip; corrosion resistance with spring temper | View grade → |
Grade Overview
The most-used Chinese spring steel for leaf springs, blades, washers and agricultural parts — good hardenability at a commodity price.
Cr-V spring steel for coil springs, leaf springs and torsion bars; the vanadium grain refinement lifts fatigue strength.
The high-silicon grade for suspension and heavy vehicle springs that must take extreme static loads without taking a set.
JIS standard Mn-Cr spring steel widely used in Japanese-vehicle leaf springs and stabiliser bars.
The European standard for valve springs, precision springs and high-fatigue coil springs with tight decarburisation control.
The North American standard leaf-spring steel — deep hardening, tough, and forgiving in heat treatment.
Simple, hard and sharp — knife blades, flat springs, washers and shims in thin and medium sections.
The Si-Mn grade behind railway bogie springs and heavy commercial vehicle suspension — very high elastic limit.
The specification for engine valve springs and high-stress precision springs — the Si-Cr chemistry resists sag at operating temperature.
Cold-rolled austenitic stainless strip for springs, clips and contacts exposed to moisture, chemicals or food-grade washdown.
What Is Spring Steel?
Spring steels are high-carbon and alloy steels designed to store elastic energy and survive millions of load cycles. The alloying pattern is consistent — carbon for strength, silicon and manganese for elasticity, chromium and vanadium for fatigue resistance and hardenability.
Our portfolio spans the Chinese GB/T 1222 series (65Mn, 60Si2MnA), the American SAE series (5160, 9260, 6150, 1095), the Japanese JIS G4801 SUP series (SUP9, SUP12) and the European EN 10089 series (51CrV4), plus stainless spring strip in 301 and 302.
Supply forms are hot-rolled spring flat bar, cold-rolled strip, spring wire and plate, in the annealed, hardened-tempered or patented condition, with decarburisation depth controlled to your standard.
How to Choose the Right Grade
Start from the duty cycle. Heavy automotive leaf springs are the classic territory of 5160, SUP9 and 65Mn. High-stress suspension and railway springs need the extra elasticity of the silicon grades 9260 and 60Si2MnA. Valve and precision springs with the highest fatigue requirements specify 50CrV4 / 51CrV4 or the Si-Cr grade SUP12 (9254). Flat springs, washers and blades in thin section use 1095, and any spring exposed to corrosion moves to 301 or 302 stainless strip. Send us the load, deflection and cycle target and we will pick the grade and supply condition.
Quality Control and Mill Certificates
Every shipment ships with an EN 10204 3.1 mill certificate covering heat chemical analysis, hardness and the mechanical test on record. On request we add: ultrasonic test on heavy bar and plate, magnetic particle inspection on machined surfaces, and third-party inspection (SGS / BV) before loading. Dimensional tolerances follow the relevant EN / ASTM / JIS standard or your drawing.
Frequently Asked Questions
Which spring steel should I use for engine valve springs?
SUP12 (9254) or 50CrV4 / 51CrV4. Both deliver the fatigue strength and heat resistance valve springs need; SUP12 is the JIS-route Si-Cr standard and the common upgrade for higher operating temperatures.
What is 65Mn equivalent to in Western standards?
65Mn corresponds closest to AISI 1566 (UNS G15660). Chemistries overlap but are not identical — for critical parts we match the certificate to your required chemistry window rather than to the paper equivalent.
Can you supply stainless spring strip in coils?
Yes. Type 301 and 302 stainless spring strip is supplied hard or spring-tempered in coils and sheets, with tensile strength graded to your specification.
Related Pages
Send your grade, form, size, quantity and destination port. You will get a firm price and lead time within one working day.
