Non-Quenched & Tempered Mechanical Structural Steel Bright Bar
Introduction:
Non-quenched & tempered mechanical structural steel bright bar is an energy-saving and environmentally friendly micro-alloyed high-precision finished steel. Micro-alloyed with V, Nb, Ti and S elements, the material adopts precise TMCP thermo-mechanical controlled rolling and cooling technology to obtain uniform ferrite-pearlite or bainite microstructure directly.
Product Overview
Non-quenched & tempered mechanical structural steel bright bar is an energy-saving and environmentally friendly micro-alloyed high-precision finished steel. Micro-alloyed with V, Nb, Ti and S elements, the material adopts precise TMCP thermo-mechanical controlled rolling and cooling technology to obtain uniform ferrite-pearlite or bainite microstructure directly. It requires no independent quenching and tempering heat treatment, effectively shortening the production cycle, reducing overall energy consumption and eliminating dimensional deviation caused by quenching deformation. 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 a diameter range of ø12–300 mm, including complete domestic standard, European standard, imported equivalent and factory customized grades: C70S6BY, 1E1497, 30MnVS6, 38MnVS6, 49MnVS3, F45MnVS, F40MnVS, F45VS, 20MnV6, HY4520, SY740, JGF45MnVS, JGF45V, HL610, HL740, JG45. Precision bright bars feature mirror smooth surface, zero oxide scale, ultra-low residual stress and accurate dimensional tolerance. Widely used for high-precision automotive crankshafts, connecting rods, steering knuckles, axles, engineering machinery heavy-duty shafts, precision fastener forgings and mass-produced mechanical structural parts.
Representative Grades
|
Grade |
Executive Standard |
Core Performance & Application |
|
C70S6BY / 49MnVS3 |
EN 10263 |
European sulfur-manganese-vanadium free-cutting non-quenched steel, high strength, good machinability; crankshafts, heavy-duty connecting rods |
|
30MnVS6 / 38MnVS6 / 20MnV6 |
EN 10263 |
Medium-low carbon V microalloy non-quenched steel, balanced strength & toughness; automobile suspension parts, small shaft forgings |
|
F40MnVS / F45MnVS / F45VS |
GB/T 15712 |
National standard sulfur-vanadium series non-quenched steel, stable ferrite-pearlite; vehicle half shafts, steering knuckles, general gear blanks |
|
1E1497 |
Foreign special automobile grade |
Bainite non-quenched steel, ultra-high fatigue strength; high-speed engine structural forgings |
|
HY4520 / JG45 |
Domestic universal non-quenched steel, low cost |
Medium-strength, for light-load machinery shafts, bolt blanks, stamping forgings |
|
SY740 / HL610 / HL740 |
Factory bainite non-quenched special steel |
High tensile strength, impact resistant; mining machinery, heavy engineering equipment parts |
|
JGF45MnVS / JGF45V |
Mill improved vanadium microalloy grades |
Uniform grain, low fluctuation of mechanical properties, batch stable for auto mass production lines |
Grade Description
-
01
MnVS series (30MnVS6/38MnVS6/F45MnVS): Mn for strength improvement, V for grain refinement, S for free-cutting performance; after hot forging + air cooling, finished mechanical properties can be reached without quenching & tempering.
-
02
C70S6BY / 49MnVS3: European high-strength non-quenched steel, high carbon matching sulfur alloy, for heavy-load automobile power components.
-
03
Bainite grades (1E1497/SY740/HL740): Controlled cooling to form bainite matrix, higher strength and fatigue life than pearlite series, suitable for high-stress working conditions.
-
04
JGF/HY/JG series: Domestic optimized non-quenched steel, stable batch performance, cost advantage for domestic auto and machinery manufacturers.
Product Specifications
|
Item |
Specific Parameters |
|
Product Form |
Hot rolled round bar;Forged round bar;Peeled bright bar |
|
Diameter Range |
ø12 mm – ø300 mm |
|
Standard Length |
3m / 6m / 9m / 12m; customized fixed-length cutting supported |
|
Delivery Condition |
Hot rolled controlled cooling (as rolled) / Normalized / Peeled & ground |
|
Surface Quality |
Mirror bright, oxide-free, crack-free, fold-free, uniform surface texture |
|
Size Tolerance |
Comply with GB/T702, EN10263 dimensional tolerance standard |
|
Straightness |
Standard grade ≤3mm/m; precision peeled bar ≤1.5mm/m |
|
Metallurgical Feature |
Uniformly distributed V carbonitride precipitates, fine equiaxed grains, low segregation |
Core Advantages
1. Process Simplification & Energy Saving: No quenching and tempering heat treatment required after forging; air cooling directly meets mechanical performance standards, greatly reducing heat treatment costs and eliminating quenching deformation defects to improve precision part yield.
2. Balanced Mechanical & Machining Performance: Micro-alloy precipitation strengthening combines with sulfur free-cutting system, achieving high tensile strength and fatigue resistance while ensuring smooth chip breaking during CNC turning and drilling.
3. Ultra-Stable Batch Consistency: EAF+LF+VD triple refining + precise TMCP controlled rolling and cooling process ensures fine and uniform grains, with extremely small performance fluctuation between heats and batches.
4. Full-Coverage Grade System: Covers low/medium-strength pearlite series and high-strength bainite series, including national, European and factory customized grades, fully matching light, medium and heavy-load precision parts.
5. Low Residual Stress & High Stability: No high-temperature quenching process, low internal residual stress of finished bright bars, stable dimensional accuracy after finishing and long-term service stability.
6. Diversified Precision Customization: Support cold drawing, centerless peeling, centerless grinding and other finishing processes, matching different precision and surface requirements of high-end mechanical parts.
Main Application Fields
-
Automobile Power System
Engine crankshafts, connecting rods, camshafts, transmission shafts, piston pins, heavy-duty bolt forgings.
-
Automobile Chassis Parts
Steering knuckles, half shafts, stabilizer bars, suspension control arm forgings, wheel hub shafts.
-
Engineering & Mining Machinery
Heavy load transmission shafts, gear blanks, hydraulic cylinder mandrels, excavator and crane structural forgings.
-
General Mechanical Equipment
Medium-strength shafts, fixture positioning pins, valve body blanks, high-strength standard fasteners.
-
Automated Forging Mass Production
Special raw materials for automatic forging lines, replacing traditional 45# and 40Cr steel to cancel heat treatment and shorten production cycle.
-
Export Automotive Supporting Parts
C70S6BY, 38MnVS6, 49MnVS3 European standard bright bars for overseas automobile supporting manufacturers.
Packaging & Services
- 1. Executive Standards: GB/T 15712 Non-quenched and tempered steel for mechanical structural parts, EN 10263; support customized technical specifications for HL, JGF and HY series special grades.
- 2. Full Inspection Items: Chemical composition analysis, tensile test, impact test, hardness test, metallographic grain and precipitate inspection, dimensional inspection; optional ultrasonic flaw detection (UT).
- 3. Material Certification: Provide EN10204 MTC 3.1 mill test certificate; support SGS, BV third-party factory inspection and certification.
- 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 & Shipment: 1 ton MOQ per grade, support mixed grades and mixed sizes container loading.
- 6. Custom Deep Processing: Optional cold drawing, centerless turning (peeling), centerless grinding, fixed-length cutting, precision straightening, shot blasting rust removal and stress-relief normalizing customization.
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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.
