Spring Steel Bright Bar
Introduction:
Spring steel bright bar is a high-precision special elastic steel finished material, produced via EAF smelting, LF refining, VD vacuum degassing and precise controlled hot rolling process. Adopting optimized C-Si-Mn-Cr-V alloy ratio, the material features ultra-high elastic limit, excellent fatigue resistance, superior temper stability and reliable hardenability.
Product Overview
Spring steel bright bar is a high-precision special elastic steel finished material, produced via EAF smelting, LF refining, VD vacuum degassing and precise controlled hot rolling process. Adopting optimized C-Si-Mn-Cr-V alloy ratio, the material features ultra-high elastic limit, excellent fatigue resistance, superior temper stability and reliable hardenability. According to customer precision and surface requirements, finished products can be selectively processed by cold drawing, centerless turning (peeling) and centerless grinding. The product covers diameter range of ø12–120 mm, including complete GB, EN and JIS mainstream grades: 65Mn, 60Si2Mn, 55Cr3, 50CrV, 51CrMnV, 51CrV4, 55CrMn, 60Si2CrVAT, SUP6, SUP7. Finished bright bars feature mirror smooth surface, no oxide scale and precise dimensional tolerance. Widely applied in high-precision automotive suspension springs, railway elastic fasteners, engineering machinery buffer springs, precision torsion bars, mold elastic parts and high-temperature heavy-load elastic components.
Representative Grades
|
Grade |
Executive Standard |
Core Performance & Application |
|
65Mn |
GB/T 1222 |
Carbon-manganese spring steel, good plasticity & low cost; small coil springs, spring washers, light-load elastic pins |
|
60Si2Mn / SUP6 |
GB/T 1222 / JIS G4801 |
Silicon-manganese spring steel, high elastic limit, max working temp ≤250℃; auto leaf springs, railway elastic clips, shock-absorbing springs |
|
SUP7 |
JIS G4801 |
High-strength silicon-manganese alloy spring steel, higher fatigue strength than SUP6; heavy-duty automotive suspension, large-diameter torsion bars |
|
55CrMn |
GB/T 1222 |
Cr-Mn spring steel, low decarburization tendency, stable strength; medium-load coil springs, agricultural machinery elastic parts |
|
55Cr3 |
EN 10089 |
European standard Cr spring steel, uniform hardening; medium-load industrial springs, cold forming elastic components |
|
50CrV / 51CrV4 |
GB/T 1222 / EN 10089 |
Cr-V series, excellent temper resistance up to 300℃, ultra-high toughness; heavy-duty large-section springs, engine valve springs |
|
51CrMnV |
GB/T 1222 |
Cr-Mn-V composite alloy, balanced strength & fatigue life; mining equipment buffer springs, heavy-duty torsion parts |
|
60Si2CrVAT |
GB/T 1222 |
High-grade high-temperature resistant spring steel, ultra-fine grain, anti-relaxation; high-speed engine springs, aerospace elastic components |
Grade Description
-
01
65Mn: Carbon manganese spring steel, high cost performance, suitable for small and medium-sized light-load elastic components.
-
02
60Si2Mn/SUP6/SUP7: Silicon-manganese spring steel. Silicon enhances the elastic limit, making it suitable for mainstream springs in automobiles and rail transportation. SUP7 has superior strength and fatigue performance compared to SUP6.
-
03
100Cr6 / SAE52100 / SUJ2: Internat55CrMn/55Cr3: Chromium-manganese and pure chromium spring steel, with low decarburization tendency and dimensional stability after heat treatment.ional universal bearing steel grades, consistent chemical composition and mechanical properties with domestic GCr15, for overseas export orders.
-
04
50CrV/51CrV4: Chromium-vanadium spring steel, with refined vanadium grains, high temperature resistance, and tempering resistance; the first choice for large-section heavy-duty springs.
-
05
51CrMnV: A chromium-manganese-vanadium composite alloy that balances hardenability and fatigue life.
-
06
60Si2CrVAT: High-end silicon-chromium-vanadium spring steel, with high purity and high-temperature relaxation resistance, used in high-end high-temperature elastic components.
Product Specifications
|
Item |
Specific Parameters |
|
Product Form |
Hot rolled round bar;Forged round bar;Peeled bright bar |
|
Diameter Range |
ø12 mm – ø120 mm |
|
Standard Length |
3m / 6m / 9m; customized fixed-length cutting supported |
|
Delivery Condition |
Hot rolled (AR) / Full annealing / Spheroidized annealing / Quenched & tempered (QT) |
|
Surface State |
Mirror bright, oxide-free, crack-free, scratch-free, ultra-smooth finish |
|
Size Tolerance |
Comply with GB/T702, EN10089, JIS G4801 standard tolerance |
|
Decarburization Control |
Strictly limited thin total decarburization layer, meets spring steel high-standard requirements |
|
Straightness |
Standard grade ≤3mm/m; precision peeled bar ≤1.5mm/m |
Core Advantages
1. Complete Global Grade System: Cover full series of GB, EN, JIS spring steels, perfectly matching light, medium, heavy load and high-temperature working conditions, realizing one-stop supply for domestic processing and export orders.
2. Superior Elasticity & Fatigue Performance: Optimized alloy formula achieves high elastic limit and yield ratio, effectively preventing permanent deformation. Fine and uniform grain structure significantly prolongs service life under cyclic alternating load.
3. Excellent Hardenability & Temper Stability: Si-Cr-V composite alloying improves through-hardening performance of medium and large-diameter bars. Cr-V grades maintain stable elasticity without softening at working temperature up to 300℃.
4. Ultra-High Metallurgical & Surface Quality: EAF+LF+VD triple smelting minimizes harmful impurities; ultra-thin decarburization layer and defect-free bright surface meet high-precision spring manufacturing standards.
5. Excellent Formability After Annealing: Annealed and spheroidized bright bars have moderate hardness, facilitating coiling, bending, cold forming and precision machining with stable process performance.
6. Flexible Precision Customization: Support three finishing processes and diversified heat treatment customization, adapting to different precision, surface and mechanical performance requirements of high-end elastic parts.
Main Application Fields
-
Automotive High-Precision Parts
Suspension coil springs, leaf springs, stabilizer bars, clutch springs, engine valve springs and shock absorber elastic components made of precision bright bars.
-
Railway Transportation Equipment
Rail elastic fasteners, bogie buffer springs, vehicle suspension springs and coupler damping precision parts.
-
Engineering & Agricultural Machinery
Excavator buffer springs, harvester elastic parts, heavy-duty torsion bars, machinery safety valve springs.
-
Mold & Hardware Precision Manufacturing
Mold ejector springs, spring washers, retaining rings, flat springs and high-strength elastic pins.
-
Heavy Industrial Equipment
Large-diameter precision torsion springs, pressure equipment buffer components and mining machinery shock-absorbing parts.
-
High-Temperature Special Fields
60Si2CrVAT high-grade bright bars for high-speed engine springs and aerospace elastic connecting components.
Packaging & Services
- 1. Executive Standards: GB/T 1222-2007, EN 10089, JIS G4801; support customized technical requirements for special spring grades.
- 2. Full Inspection Items: Chemical composition analysis, tensile test, hardness test, decarburization layer measurement, metallographic grain inspection, fatigue performance sampling test; optional ultrasonic flaw detection (UT), magnetic particle inspection (MPI).
- 3. Material Certification: EN10204 MTC 3.1 mill test certificate; SGS, BV third-party factory inspection and certification available.
- 4. Professional Exclusive Packaging for Bright Bars: Adopts special scratch-proof and rust-proof precision packaging for bright bars, wrapped with thickened waterproof film on the outer layer and firmly bundled and fixed. High-precision and long-size products can be customized with solid wooden box packaging, completely avoiding collision, scratches, deformation and rust during transportation, suitable for long-distance sea and land transportation.
- 5. MOQ: 1 ton per grade; mixed grades and mixed sizes can be loaded in one container.
- 6. Custom Processing: Optional cold drawing, centerless turning (peeling), centerless grinding, spheroidizing annealing, quenching & tempering, fixed-length cutting, shot blasting rust removal and stress relief heat treatment.
Send Message
Products +
Contact Us
- WhatsApp: +86-185 9567 2991
- Email: martinliu@rongtianmetal.com
- Tel: +86-185 9567 2991
- Address: 8F, Bldg 2, Jinke Zhihui Valley No. 65 Hongyuan Rd., Jinshui Dist. Zhengzhou, China.
