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China factory - JIANGSU MITTEL STEEL INDUSTRIAL LIMITED

JIANGSU MITTEL STEEL INDUSTRIAL LIMITED

  • China,Wuxi ,Jiangsu
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  3. AISI 4340 Steel Round Bar - High Tensile Strength, Shock and Impact Resistant,
China AISI 4340 Steel Round Bar - High Tensile Strength, Shock and Impact Resistant,
China AISI 4340 Steel Round Bar - High Tensile Strength, Shock and Impact Resistant,

  1. China AISI 4340 Steel Round Bar - High Tensile Strength, Shock and Impact Resistant,
  2. China AISI 4340 Steel Round Bar - High Tensile Strength, Shock and Impact Resistant,
  3. China AISI 4340 Steel Round Bar - High Tensile Strength, Shock and Impact Resistant,
  4. China AISI 4340 Steel Round Bar - High Tensile Strength, Shock and Impact Resistant,
  5. China AISI 4340 Steel Round Bar - High Tensile Strength, Shock and Impact Resistant,
  6. China AISI 4340 Steel Round Bar - High Tensile Strength, Shock and Impact Resistant,
  7. China AISI 4340 Steel Round Bar - High Tensile Strength, Shock and Impact Resistant,

AISI 4340 Steel Round Bar - High Tensile Strength, Shock and Impact Resistant,

  1. MOQ： 1 Ton
  2. Price： US $720-1,430 / Ton
  3. Get Latest Price
Diameter Range 6-630mm
Carbon Content 0.38-0.43%
Manganese Content 0.60-0.80%
Phosphorus Content 0.035%
Sulfur Content 0.040%
Silicon Content 0.15-0.35%
Nickel Content 1.65-2.00%
Chromium Content 0.70-0.90%
Molybdenum Content 0.20-0.30%
Tensile Strength 930-1080 MPa
Yield Strength 740 MPa
Elongation 12%
Impact Resistance 47 J
Brinell Hardness 269-331 HB
Thermal Conductivity 44.5 W/mK

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  1. Product Details
  2. Company Details

Product Specification

Diameter Range 6-630mm Carbon Content 0.38-0.43%
Manganese Content 0.60-0.80% Phosphorus Content 0.035%
Sulfur Content 0.040% Silicon Content 0.15-0.35%
Nickel Content 1.65-2.00% Chromium Content 0.70-0.90%
Molybdenum Content 0.20-0.30% Tensile Strength 930-1080 MPa
Yield Strength 740 MPa Elongation 12%
Impact Resistance 47 J Brinell Hardness 269-331 HB
Thermal Conductivity 44.5 W/mK
High Light High Tensile Strength AISI 4340 Steel Round Bar ，Shock and Impact Resistant 40CrNiMoA Round Bar ，Wear and Abrasion Resistant SNCM439 Alloy Steel Bar
40CrNiMoA BS S535/AMS 6350 AISI 4340 Round Bar JIS Sncm439
AISI 4340 steel is a medium carbon, low alloy steel known for its exceptional toughness and strength in relatively large sections. As a nickel chromium molybdenum steel, 4340 alloy steel is typically supplied hardened and tempered in the tensile range of 930-1080 Mpa. This material offers excellent shock and impact resistance along with superior wear and abrasion resistance in the hardened condition.
Specifications and Standards
Country USA Britain Britain Japan
Standard ASTM A29 EN 10250 BS 970 JIS G4103
Grades 4340 36CrNiMo4/1.6511 EN24/817M40 SNCM 439/SNCM8
Chemical Composition
Standard Grade C Mn P S Si Ni Cr Mo
ASTM A29 4340 0.38-0.43 0.60-0.80 0.035 0.040 0.15-0.35 1.65-2.00 0.70-0.90 0.20-0.30
EN 10250 36CrNiMo4/1.6511 0.32-0.40 0.50-0.80 0.035 0.035 <=0.40 0.90-1.20 0.90-1.2 0.15-0.30
BS 970 EN24/817M40 0.36-0.44 0.45-0.70 0.035 0.040 0.1-0.40 1.3-1.7 1.00-1.40 0.20-0.35
JIS G4103 SNCM 439/SNCM8 0.36-0.43 0.60-0.90 0.030 0.030 0.15-0.35 1.60-2.00 0.60-1.00 0.15-0.30
Mechanical Properties
Condition Ruling Section (mm) Tensile Strength (MPa) Yield Strength (MPa) Elongation (%) Izod Impact (J) Brinell Hardness
T 250 850-1000 635 13 40 248-302
T 150 850-1000 665 13 54 248-302
U 100 930-1080 740 12 47 269-331
V 63 1000-1150 835 12 47 293-352
W 30 1080-1230 925 11 41 311-375
X 30 1150-1300 1005 10 34 341-401
Y 30 1230-1380 1080 10 24 363-429
Z 30 1555- 1125 5 10 444-
Thermal Properties
Properties Metric Imperial
Thermal expansion co-efficient 12.3 µm/m°C 6.83 µin/in°F
Thermal conductivity 44.5 W/mK 309 BTU in/hr.ft².°F
Heat Treatment Processes
Forging
Preheat 4340 steel to 1150°C - 1200°C maximum for forging, holding until temperature is uniform throughout the section. Do not forge below 850°C. Following forging, cool the workpiece as slowly as possible in sand or dry lime to prevent cracking.
Stress Relieving
Heat to 600°C - 650°C, hold until uniform temperature, soak for 1 hour per 25mm section, and cool in still air.
Annealing
Full anneal at 844°C (1550°F) followed by controlled furnace cooling at a rate not faster than 10°C (50°F) per hour down to 315°C (600°F), then air cool.
Tempering
Temper at 232°C (450°F) for 260-280 ksi strength range, or at 510°C (950°F) for 125-200 ksi strength range. Avoid tempering between 250°C - 450°C due to temper brittleness.
Surface Hardening
Pre-hardened 4340 steel can be surface hardened by flame or induction hardening, achieving case hardness exceeding Rc 50. Heat quickly to 830°C - 860°C followed by oil or water quenching.
Nitriding
Hardened and tempered 4340 can be nitrided at 500°C - 530°C for 10-60 hours, achieving surface hardness of 600-650HV with minimal effect on core tensile strength.
Machining and Welding
Machining is best performed in the annealed or normalized and tempered condition. In high strength conditions (200 ksi or greater), machinability decreases to 25-10% of the annealed condition. Welding in hardened and tempered condition is not recommended. If necessary, pre-heat to 200-300°C and stress relieve at 550-650°C after welding.
Applications
  • Aircraft Landing Gear
  • Automotive Components
  • Oil and Gas Drilling Equipment
  • Forging Applications
  • Machine Building
  • Power Transmission Gears and Shafts
  • Heavy Duty Shafts, Axles, Spindles
  • Couplings, Pins, Chucks, Molds
Available Sizes and Conditions
Round Bar Diameter: 12-380mm
Available in round bars, flat bars, plates, and blocks in various conditions including pre-hardened, hot rolled, annealed, quenched and tempered, with surface conditions from black to pre-machined, grinding, and polish.
Product Images
AISI 4340 steel round bars inventory 4340 alloy steel material close-up Steel bars quality inspection Manufactured steel components
Why Choose Our 4340 Steel
Quality Assurance
Materials sourced directly from government-owned steel mills with ISO 9001 certified quality management system.
Timely Delivery
Speedy processing and delivery for both raw materials and finished products with machining or heat treatment.
Comprehensive Services
Value-adding services including metal cutting, sizing, machining, heat treatment, and sawing for any quantity.
Extensive Inventory
Unique inventory of specialty steel with orders of any size or length accommodated.
Additional Product Images
Steel processing facility Quality control inspection Finished steel products

Company Details

Bronze Gleitlager

,

Bronze Sleeve Bushings

 and 

Graphite Plugged Bushings

 from Quality China Factory

  • Business Type:

    Manufacturer,Distributor/Wholesaler,Exporter

  • Total Annual:

    >1000000

  • Employee Number:

    >100

  • Ecer Certification：

    Verified Supplier

Our company is located in Wuxi City, China, we are a stainless steel plate, seamless steel pipe, round steel, steel belt, decorative pipe and other products distribution wholesale private enterprise. Our company operates stainless steel plate, seamless steel pipe, round steel, steel belt, decorative... Our company is located in Wuxi City, China, we are a stainless steel plate, seamless steel pipe, round steel, steel belt, decorative pipe and other products distribution wholesale private enterprise. Our company operates stainless steel plate, seamless steel pipe, round steel, steel belt, decorative...

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Get in touch with us

  • Reach Us
  • JIANGSU MITTEL STEEL INDUSTRIAL LIMITED
  • No.283-1, Youyi Middle Road, Xishan District, Wuxi City, Jiangsu Province
  • https://www.stainless-strips.com/

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