Precision 65Mn Spring Steel Strip for Automotive/Machinery Applications Quenched & Tempered AISI 1566 High Tensile Strength Steel Coil
65Mn Spring Steel Coil - Full-Spec Technical Data for Export
1. Basic Information & Standard Specifications
65Mn is a carbon spring steel grade under China's GB standard (GB/T 1222-2021/2007), pronounced "65 Manganese". Its equivalent international grades are ASTM 1566/AISI 1066, DIN CK67, JIS SUP6/SWRH67A, and UNS G10660.
Executive Standards: GB/T 1222-2021 (Spring Steel), GB/T 3525-2008 (Hot-Rolled Spring Steel Strip)
Product Form: Cold Rolled/Hot Rolled Spring Steel Coil
Delivery Condition: Annealed, Quenched & Tempered (Q&T), Cold Drawn
2. Chemical Composition (%, by weight)
| Element |
C |
Mn |
Si |
P |
S |
Cr |
Ni |
Cu |
| Content |
0.62~0.70 |
0.90~1.20 |
≤0.35 |
≤0.035 |
≤0.035 |
≤0.25 |
≤0.25 |
≤0.25 |
*Source: Specified in GB/T 1222-2021 Standard*
3. Core Mechanical Properties
| Property Index |
Annealed State |
Quenched & Tempered (Q&T) |
Unit |
| Tensile Strength (Rm) |
≥785 |
≥1080 |
MPa |
| Yield Strength (Rp0.2) |
≥450 |
≥930 |
MPa |
| Elongation (A) |
≥14 |
≥8 |
% |
| Reduction of Area (Z) |
≥30 |
≥30 |
% |
| Hardness |
≤250HB |
40~48HRC |
- |
*Quenching Process: Oil quenching at 830~860ºC; Tempering Process: Air cooling after heat preservation at 420~520ºC*
4. Coil Specification Parameters
| Parameter |
Standard Range |
Customizable Range |
Remarks |
| Thickness |
0.08~4.0mm |
0.05~6.0mm |
Available for both cold and hot rolling |
| Width |
5~400mm |
5~600mm |
Slittable to narrow specifications |
| Inner Diameter |
508mm/610mm |
300~1200mm |
Standard industrial inner diameter |
| Outer Diameter |
800~2000mm |
600~2500mm |
Calculated by weight |
| Single Coil Weight |
0.5~5 Tons |
0.1~10 Tons |
Customized packaging |
| Surface Treatment |
Mill Finish, Blueing, Galvanizing |
Customizable per customer requirements |
Anti-corrosion treatment |
*Typical Specifications: 1.0mm×100mm×C, 2.0mm×200mm×C (C indicates coil form)*
5. Heat Treatment Process & Performance Optimization
5.1 Annealing Treatment
Temperature: 790~810ºC, slow cooling with furnace after heat preservation
Purpose: Reduce hardness (≤250HB), improve ductility for easy processing
5.2 Quenching + Tempering (Key Process)
Quenching: Oil cooling at 830~860ºC to obtain martensite structure
Tempering: Air cooling at 420~520ºC to obtain tempered sorbite
Effect: Hardness 40~48HRC, maximizing elastic limit and fatigue strength
5.3 Surface Strengthening
Shot Peening: Improve surface compressive stress and extend spring fatigue life
Blueing: Form Fe3O4 protective film for corrosion resistance
6. International Standard Equivalents
| China Standard |
USA Standard |
Germany Standard |
Japan Standard |
UK Standard |
France Standard |
| 65Mn |
ASTM 1566/AISI 1066 |
DIN CK67 |
JIS SUP6/SWRH67A |
BS 080A67 |
NF XC65 |
*Note: Slight differences in chemical composition and mechanical properties may exist; corresponding standards should be specified for export.*
7. Application Fields
Spring Products: Small flat springs, wire springs, seat cushions, clockwork springs, valve springs, clutch springs, brake springs
Tools & Blades: Scrapers, blades, woodworking saw blades, surgical instruments
Automotive Components: Shock absorber springs, suspension system springs, brake shoes
Mechanical Accessories: Elastic washers, circlips, spring clamps, safety pins
Others: Tape measure steel strips, manometer springs, instrument elastic components
8. Product Advantages & Features
High Elastic Limit: Manganese element improves hardenability; φ12mm steel can be fully oil-quenched
Excellent Fatigue Performance: Suitable for high-frequency reciprocating working conditions
Low Surface Decarburization Tendency: Superior to silicon-based spring steel with good surface quality after heat treatment
Cost-Effective: More competitive price than alloy spring steel, suitable for mass production
Good Machinability: Easy to cut in annealed state with excellent cold deformation capacity
9. Key Export Information
9.1 Packaging Standard
Inner Packaging: Rust-proof paper + plastic film wrapping
Outer Packaging: Wooden pallet + steel strip binding, complying with IPPC export standard
Marking: Clearly indicate material, specification, heat treatment state, batch number, gross weight/net weight
9.2 Certification Documents
Material Test Certificate (MTC), SGS Report, ISO 9001 Certification
Export Customs Declaration: HS Code 7225.99.90 (Spring Steel Coils)
9.3 Minimum Order Quantity (MOQ)
1 Ton; can be split into small coils for packaging as per customer requirements
10. Professional English Product Titles (SEO-Optimized for B2B Platforms)
The following are high-conversion product title templates, adjustable according to specific specifications:
10.1 Standard Type
65Mn Spring Steel Coil, ASTM 1566 Cold Rolled, 1.0mm×100mm×C, Quenched & Tempered
High Carbon 65Mn Spring Steel Coil, DIN CK67 Equivalent, Annealed State, 2.0mm×200mm×C
10.2 Application-Oriented
65Mn Automotive Suspension Spring Steel Coil, 1.5mm×150mm×C, High Fatigue Resistance
Precision 65Mn Flat Spring Steel Coil for Electronic Devices, 0.5mm×50mm×C, Blue Surface
10.3 Feature-Emphasized
65Mn High Elasticity Spring Steel Coil, 45HRC Hardness, 3.0mm×300mm×C, Oil-Quenched
Corrosion-Resistant 65Mn Spring Steel Coil, Zinc-Plated, 0.8mm×80mm×C, AISI 1066 Grade
11. Order & Technical Consultation
Supply Capacity: 1000 Tons/Month; Delivery within 7 days for regular specifications, 15 days for customized specifications
Payment Terms: T/T (30% Advance + 70% Against B/L Copy), L/C, D/P
Ports: Major ports such as Qingdao, Shanghai, Tianjin
Quality Assurance: Complying with GB/T 1222-2021 standard, providing material certificate and dimensional tolerance report
AISI 1566 (UNS G15660) is an American standard high carbon manganese steel, corresponding to the national standard 65Mn spring steel. It belongs to high-quality carbon structural steel and is commonly used in springs and high-strength wear-resistant parts.
Common uses:
Automobiles: suspension springs, valve springs, torsion bars, clutch springs
Machinery: leaf springs, coil springs, high-strength bolts, shafts
Tools/Agricultural Machinery: Blades, Cutting Tools, Ploughshares, Rakes, Teeth
Domestic and international comparison (approximate)
China: 65Mn (GB/T 1222)
Japan: SUP7, S65C
Germany: 65Mn (DIN)
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