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AISI 4140 Round Bars

Buy Top Quality AISI 4140 Round Bar at Ferrite Structural Steels Pvt Ltd. – India’s Leading Supplier, Manufacturer and Exporter of MS Round Bars.

AISI 4140 Round Bars

AISI 4140 round bars are a high-strength alloy steel popular for their excellent toughness, high fatigue strength, and abrasion resistance. Composed of chromium, molybdenum, and manganese, this steel is known for its ability to withstand the rigors of extreme environments and demanding applications. AISI 4140 is often used in the automotive, oil and gas, and aerospace industries for components such as gears, bolts, and crankshafts that require high tensile strength and toughness. Its versatility also extends to applications in tooling and dies where resistance to wear and impact is crucial.

Ferrite Structural Steels Pvt Ltd., as a major manufacturer and supplier, excels in providing AISI 4140 round bars that meet global quality standards. The company leverages advanced manufacturing technologies and stringent quality control measures to ensure that each product delivers superior performance and reliability. With a focus on customer satisfaction and technical excellence, Ferrite Structural Steels Pvt Ltd. continues to be a leader in the steel industry, offering innovative solutions and tailored products to meet the complex demands of its diverse client base.

AISI 4140 Round Bar Specifications

Product Name AISI 4140 Round Bar
Brand Ferrite Structural Steels Pvt. Ltd.
Minimum Order Quantity 1 Ton
Material Mild Steel
Finish Hot-rolled, galvanized, or as specified by customer

AISI 4140 Round Bar Size Chart

Size (mm) Average Weight (KG/MTR) Average Weight (KG/FT)
10 0.62 0.18
12 0.9 0.3
14 1.2 0.4
16 1.6 0.5
18 2 0.6
20 2.5 0.8
22 3 0.9
24 3.56 1.08
25 3.9 1.2
28 4.8 1.5
30 5.55 1.69
32 6.3 1.9
34 7.14 2.18
36 8 2.44
40 9.9 3
45 12.49 3.81
50 15.4 4.7
56 19.34 5.89
60 22 6.8

 

AISI 4140 Equivalent grades

Country USA German British Japan China Australia
Standard ASTM A29 DIN 17200 BS 970 JIS G4105 GB/T 3077 AS 1444
Grades 4140 1.7225/
42CrMo4		 42CrMo4 SCM440 42CrMo 4140

 

AISI 4140 Chemical composition

Standard Grade C Mn P S Si Cr Mo
ASTM A29 4140 0.38-0.43 0.75-1.00 0.035 0.040 0.15-0.35 0.8-1.10 0.15-0.25
EN 10083/EN 10250 42CrMo4/1.7225 0.38-0.45 0.6-0.9 0.035 0.035 0.4 0.9-1.2 0.15-0.30
JIS G4105 SCM440 0.38-0.43 0.60-0.85 0.03 0.03 0.15-0.35 0.9-1.2 0.15-0.30

 

AISI 4140 Mechanical Properties

Properties Metric Imperial
Tensile strength 655 MPa 95000 psi
Yield strength 415 MPa 60200 psi
Bulk modulus (typical for steel) 140 GPa 20300 ksi
Shear modulus (typical for steel) 80 GPa 11600 ksi
Elastic modulus 190-210 GPa 27557-30458 ksi
Poisson’s ratio 0.27-0.30 0.27-0.30
Elongation at break (in 50 mm) 25.70% 25.70%
Hardness, Brinell 197 197
Hardness, Knoop (converted from Brinell hardness) 219 219
Hardness, Rockwell B (converted from Brinell hardness) 92 92
Hardness, Rockwell C (converted from Brinell hardness. Value below normal HRC range, for comparison purposes only) 13 13
Hardness, Vickers (converted from Brinell hardness) 207 207
Machinability (based on AISI 1212 as 100 machinability) 65 65

Key Features and Benefits

  1. Alloy Steel Composition: AISI 4140 is an alloy steel that includes chromium, molybdenum, and manganese, enhancing its overall strength, toughness, and wear resistance.
  2. High Tensile Strength: These bars boast high tensile strength, making them suitable for applications requiring robust, durable materials.
  3. Excellent Toughness: AISI 4140 maintains excellent toughness at high hardness, providing essential durability under impact and stress.
  4. Outstanding Hardness and Abrasion Resistance: Hardened and tempered AISI 4140 can achieve high hardness levels, contributing to excellent abrasion resistance.
  5. Weldability: With the proper preheating and post-weld heat treatment, AISI 4140 can be welded with relative ease, allowing for the construction of complex assemblies.
  6. Durability in Harsh Conditions: The robust nature of AISI 4140 ensures that it can withstand harsh operating conditions, making it ideal for heavy-duty applications.
  7. Long Service Life: The high strength and wear resistance of AISI 4140 contribute to a longer service life of parts and components, reducing downtime and maintenance costs.
  8. Cost-Effectiveness: Although it is an alloy steel, AISI 4140 is relatively cost-effective for applications requiring its specific properties, providing good value for the investment.
  9. Customizability Through Heat Treatment: The ability to tailor the mechanical properties through various heat treatments allows engineers to optimize AISI 4140 for specific uses, enhancing performance in targeted applications.

Applications of AISI 4140 Bar

Manufacturing and Industrial:

  • Gears and Shafts: Commonly used in the production of industrial gears and shafts where strength and impact resistance are critical.
  • Axles and Bolts: Ideal for creating axles, bolts, and other hardware that require a medium level of strength and substantial impact resistance.
  • Crankshafts: Used in manufacturing crankshafts for vehicles and machines, providing the necessary toughness and durability.

Engineering and Construction:

  • Building Support Structures: Suitable for construction applications that demand high strength, such as support beams, frames, and structural components.
  • Heavy Equipment Manufacturing: Used in the manufacturing of components for heavy machinery used in construction and agriculture.

Oil and Gas Industry:

  • Oil Drill Bits and Tooling: AISI 4140 is used in the oil and gas industry for producing drill bits and other tooling that require robustness against impacts and stress.

Agricultural Equipment:

  • Farm Machinery Components: Employed in the production of durable components for agricultural machinery, such as gears, axles, and shafts.

Sporting Goods:

  • Sports Equipment: Used in the manufacture of high-strength sporting equipment like weightlifting bars, due to its ability to handle stress and impact.

Metal Products:

  • Forged Metal Goods: AISI 4140 is often chosen for the forging of metal products like flanges, fittings, and valves that need medium carbon steel with good strength.
FAQs — AISI 4140 Round Bars

AISI 4140 Round Bars: Frequently Asked Questions

Straight answers on sizes, thickness, weight, grades, MTC, pricing and ordering — so your enquiry is specification-ready before you send it.

01
What is AISI 4140 Round Bars?
AISI 4140 Round Bars are chromium-molybdenum alloy steel round bars selected for strength, toughness and hardenability. The exact diameter, grade, standard, supply condition and intended use must be stated because the commercial product name alone does not establish chemical, mechanical, dimensional or heat-treatment requirements.
02
What are the main applications of AISI 4140 Round Bars?
Common applications include shafts, gears, bolts, tools, dies and heavy machinery components. Suitability depends on the component design, loads, environment, machining allowance, heat treatment and governing code. Final selection must follow the approved drawing, BOQ, end-user specification and responsible engineer’s approval.
03
Which diameters are listed for AISI 4140 Round Bars?
The live round-bar chart lists 10, 12, 14, 16, 18, 20, 22, 24, 25, 28, 30, 32, 34, 36, 40, 45, 50, 56 and 60 mm. These published entries are not a guarantee of current stock. Confirm the exact diameter, grade, length, condition and quantity, particularly when a machining drawing requires an unlisted size or minimum clean-up allowance.
04
How should I specify the diameter and tolerance for AISI 4140 Round Bars?
State the nominal diameter in millimetres, applicable diameter tolerance, ovality if relevant, straightness and surface condition. For machined parts, add the finished component size and machining allowance. Bright, peeled, ground and hot-rolled bars may have different dimensional expectations.
05
What standard lengths are available for AISI 4140 Round Bars?
The reviewed page does not publish a fixed length range. Availability should be confirmed for the requested diameter, grade and quantity. State exact or random length, permissible tolerance, cut-length schedule, end condition and whether each piece must be identified to a drawing item.
06
How is AISI 4140 Round Bars weight per metre calculated?
For a solid steel round bar, theoretical weight in kg/m is approximately diameter squared x 0.006165, using nominal dimensions and a typical steel density. Actual or invoiced weight may differ because of diameter tolerance, density, scale, length and the agreed commercial basis.
07
Can I get a AISI 4140 Round Bars weight chart?
Yes. The live page provides average kg/m and kg/ft values for listed diameters. Use them for estimation, then confirm the quotation basis and applicable dimensional tolerances. For alloy or special-condition material, ask whether the supplier uses theoretical or actual weighment.
08
What is the AISI 4140 Round Bars price per kg?
The price per kg requires a dated quotation and varies with grade, diameter, quantity, supply condition, finish, testing, cutting, packing, freight and taxes. Alloy surcharge and heat-treatment condition can be important for engineering grades. Send a complete specification for a comparable rate.
09
How is the AISI 4140 Round Bars price per tonne determined?
Price per tonne depends on the exact grade and standard, diameter mix, bar length, total tonnage, condition, certification, inspection and destination. Confirm whether cutting, heat treatment, testing, packing, freight and GST are included and check the quotation validity.
10
What is the MOQ for AISI 4140 Round Bars?
The live page states a minimum order quantity of 1 tonne. Actual order acceptance remains subject to the required diameter, grade, condition and availability. For mixed-diameter orders, give the piece count or weight for each line item so every size can be reviewed.
11
Is AISI 4140 Round Bars available from ready stock?
Stock must be confirmed for the exact diameter, grade, standard, length, finish, condition and quantity. A live product page or size chart does not establish immediate availability. State any mill or make preference, MTC requirement, inspection plan and required delivery date.
12
Can an MTC be supplied with AISI 4140 Round Bars?
Request the mill test certificate at enquiry stage and state the required document type. It should identify the material, heat or batch, grade, standard and reported chemistry and mechanical results where applicable. Heat-treatment condition, hardness and traceability requirements should be agreed before ordering.
13
Which heat-treatment condition should be ordered?
State annealed, normalised or quenched-and-tempered condition, required hardness range, diameter and mechanical-property specification. State whether the material is annealed, normalised or quenched and tempered and specify the required hardness range. Machining allowance and subsequent heat treatment should be planned with the component manufacturer.
14
Can AISI 4140 Round Bars be cut, machined, threaded or heat treated?
Processing can be reviewed against the drawing, grade, condition and quantity. Provide cut lengths, tolerances, thread details, machining allowance and required heat treatment or hardness. Final component properties cannot be guaranteed from the bar designation alone; the approved manufacturing route controls the result.
15
Can AISI 4140 Round Bars be replaced with an equivalent grade?
Do not substitute from a web equivalence table alone. Compare full chemistry limits, mechanical properties, diameter-dependent requirements, delivery condition, hardenability, impact quality, heat treatment and certification. Any alternative requires written approval from the responsible engineer or end user before supply.
16
Can I buy AISI 4140 Round Bars from a supplier in Mumbai or Navi Mumbai?
Ferrite lists its head office in Mumbai and a facility address at Kalamboli, Navi Mumbai. Provide delivery postcode, longest length, total tonnage, unloading constraints and required date so availability and logistics can be reviewed for Mumbai, Navi Mumbai and Maharashtra.
17
Can AISI 4140 Round Bars be supplied across India?
The website states nationwide supply. India-wide enquiries should include the consignee postcode, grade, diameter, length, tonnage, packing and delivery schedule. Long-bar freight can materially affect landed price, so compare offers on the same ex-works or delivered basis.
18
Does Ferrite handle export enquiries for AISI 4140 Round Bars?
Export requirements can be reviewed against the requested specification and quantity. Provide destination port and country, Incoterm, grade, standard, diameter, length, tonnage, condition, packing, MTC and inspection requirements. Shipping programme and documentation must be confirmed for the specific order.
19
How should quotations from AISI 4140 Round Bars suppliers be compared?
Compare the exact grade, standard, diameter tolerance, length, condition, origin or make if specified, MTC, inspection, cutting, packing, freight, taxes and delivery basis. A lower rate is not comparable if the offered condition, certification or heat-treatment scope differs.
20
What details are needed for a fast AISI 4140 Round Bars quotation?
Send product name, complete grade and standard, diameter, length, piece quantity and total tonnage. Add finish and delivery condition, tolerance, make preference, MTC, inspection or ultrasonic testing, cutting drawing, delivery postcode or destination port, Incoterm and required delivery date.

Why Choose Ferrite’s AISI 4140 Round Bar?

Choosing Ferrite’s AISI 4140 Round Bars means selecting a product known for its reliability, durability, and performance in challenging environments. At Ferrite Structural Steels Pvt Ltd, we specialize in producing high-quality AISI 4140 Round Bars using meticulous manufacturing processes that adhere to strict quality standards. Each bar undergoes rigorous testing to ensure it meets our high standards, guaranteeing that our customers receive only the best products.

We are committed to providing not only top-quality steel but also exceptional customer service. Our team is dedicated to assisting you in finding the perfect steel solutions for your projects, ensuring that all your specifications and requirements are met efficiently. Contact us today to discuss your needs and request a quote. We are here to support your projects with our reliable and high-performing products.

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