Source 4140 steel bar for machining, shaft production, gears, industrial components and heavy-duty equipment. We support procurement of AISI 4140 alloy steel bar in round, flat and square sections, with stock availability, cut-to-length options and bulk supply arrangements confirmed against your requirements.
- Grade: AISI 4140 / SAE 4140
- Product Forms: Round Bar, Flat Bar, Square Bar and Forged Bar
- Supply Conditions: Hot Rolled, Annealed and Quenched & Tempered, subject to availability
- Size Range: Common commercial dimensions with customized sizes available
- Documentation: Material Test Certificate (MTC) available by agreement
- Orders: Stock purchases and bulk orders
Contact us with your required dimensions, quantity and delivery destination to check availability and obtain a quotation.
4140 Steel Bar Stock and Size Range
We supply 4140 steel bar stock for steel distributors, machining companies, component manufacturers and industrial buyers. Round bar is the principal product form, with flat, square and forged bar available subject to sourcing and specification requirements.
| Product Form | Common Commercial Size Range | Standard Length Options |
|---|---|---|
| 4140 Steel Round Bar | Diameter: 10–300 mm | 3–6 m |
| 4140 Steel Flat Bar | Thickness: 10–100 mm; width: 20–300 mm | 3–6 m |
| 4140 Steel Square Bar | Side length: 10–150 mm | 3–6 m |
| 4140 Alloy Steel Forged Bar | Diameter or section size: 100–600 mm, subject to forging route | Specified lengths or cut lengths |
The ranges above are indicative commercial sourcing ranges, not guaranteed stock dimensions. Actual availability depends on the production route, grade specification, section size and material condition. Customized dimensions and cut lengths can be discussed for individual orders.
4140 Steel Bar Specifications
| Specification Item | Supply Details |
|---|---|
| Material Grade | AISI 4140 / SAE 4140 |
| Material Type | Chromium-Molybdenum Alloy Steel |
| Equivalent Designations | 42CrMo4 / 1.7225, subject to specification verification |
| Product Forms | Round Bar, Flat Bar, Square Bar, Forged Bar |
| Manufacturing Route | Hot Rolled, Forged or Other Agreed Supply Routes |
| Heat Treatment | Annealed, Normalized or Quenched & Tempered, subject to availability |
| Surface Condition | As Rolled, Peeled, Turned or Machined, where available |
| Size Range | Common commercial dimensions; customized sizes available |
| Length | Standard commercial lengths or cut-to-length supply |
| Dimensional Tolerance | According to the applicable product specification and order |
| MOQ | No fixed MOQ for available stock; other quantities are negotiable according to purchasing requirements |
| Inspection Documents | Material Test Certificate (MTC) and agreed test results |
| Applicable Standards | ASTM A29/A29M or other agreed specifications, subject to product form and supply route |
4140 Steel Bar Applications
4140 alloy steel bar is commonly purchased for machined components and industrial parts requiring strength, hardenability and reliable performance under mechanical loads.
- Shafts and Axles: Round bar for drive shafts, transmission shafts, axles and spindle components.
- Gears and Couplings: Bar stock for machined gears, couplings, pinions and power-transmission parts.
- Machinery Components: Raw material for pins, bolts, connecting components and other load-bearing machine parts.
- Oil and Gas Equipment: Selected mechanical components and machined parts for drilling and industrial equipment, subject to application-specific requirements.
- Heavy Equipment: Components for construction machinery, agricultural equipment and material-handling systems.
- Tooling and Fixtures: Round, flat and square bar for jigs, fixtures, tooling bases and other machined components.
- Forged Components: Forged bar stock for larger or heavier-duty components where the required dimensions and material condition are available.
Chemical Composition
Typical AISI 4140 chemical composition limits are shown below. The applicable product specification and material certificate govern final acceptance.
| C (%) | Mn (%) | Si (%) | Cr (%) | Mo (%) | P (%) | S (%) |
|---|---|---|---|---|---|---|
| 0.38–0.43 | 0.75–1.00 | 0.15–0.35 | 0.80–1.10 | 0.15–0.25 | ≤ 0.035 | ≤ 0.040 |
Mechanical Properties
Mechanical properties vary with heat treatment, section size and testing requirements. The following are indicative reference values for annealed 4140 steel and should not be treated as guaranteed values for every supply condition.
| Condition | Tensile Strength | Yield Strength | Elongation | Hardness |
|---|---|---|---|---|
| Annealed | Approx. 655 MPa | Approx. 415 MPa | Approx. 25% | Approx. 197 HB |
For quenched and tempered 4140 steel bar, specify the required tensile strength, yield strength and hardness range in the inquiry. Acceptance values should be agreed against the applicable standard, bar size and material test requirements.
4140 Steel Bar Packaging and Transportation
- Bundling: Steel bars bundled securely for handling and shipment.
- Surface Protection: Protective wrapping or other suitable measures can be arranged according to surface condition and transportation requirements.
- Marking: Grade, dimensions, bundle identification and shipment marks as agreed.
- Export Packing: Packing arrangements tailored to shipment method, destination and buyer requirements.
- Loading: Bundled cargo arranged according to bar length, shipment weight and container or break-bulk requirements.
- Documentation: Commercial shipping documents and agreed material certificates supplied for export orders.
Packing and loading arrangements are confirmed before dispatch to help maintain product identification and reduce handling damage during transportation.
Request a 4140 Steel Bar Supply Quotation
Send your requiry including 4140 steel bar grade, section dimensions, material condition and order quantity to check available stock and sourcing options. We can coordinate specifications, inspection documentation, cutting requirements and export shipment arrangements according to your purchasing needs.