Hot-Wrought Round Bar
Solid 4340 bars with an as-rolled surface, ordered by diameter and length.
Global Steel Supply & Processing
SAE / AISI 4340 · UNS G43400 · ASTM A322
Source nickel-alloyed 4340 round steel bar for heavy shafts, gears and industrial equipment. Share your diameter, length, supply condition, tonnage and destination port for a factory quotation.
See specifications and supply conditions ↓Use your grade, bar diameter, requested condition and inspection documents to obtain a comparable quotation.
| Steel grade | AISI / SAE 4340 |
| UNS number | G43400 |
| Alloy family | Nickel-chromium-molybdenum (Ni-Cr-Mo) low-alloy steel |
| Hot-wrought bar standard | ASTM A322-24 |
| General bar requirements | ASTM A29/A29M-23, where referenced by the order |
| Quenched & tempered bar | ASTM A434/A434M-24, where specified by strength class and size |
| Product forms | Solid round bars; square, hexagonal and flat shapes subject to confirmed availability |
| Delivery conditions | Hot-wrought, annealed, normalized, or quenched & tempered as quoted |
| Diameter and length | Supplied against your size schedule and confirmed stock / production capability |
| Documentation | Chemical analysis, mechanical tests, hardness, dimensional checks and MTC as ordered |
Select the surface and supply state that suit your turning, machining and heat-treatment requirements.
Solid 4340 bars with an as-rolled surface, ordered by diameter and length.
Specify the measured diameter, finish and surface allowance for your machining schedule.
Inspect the appearance of bar ends and provide your required cutting allowance.
Review the nickel, chromium and molybdenum content alongside the carbon range. Request the actual heat analysis with your MTC.
| Element | Mass Fraction |
|---|---|
| Carbon (C) | 0.38–0.43% |
| Manganese (Mn) | 0.60–0.80% |
| Silicon (Si) | 0.15–0.35% |
| Nickel (Ni) | 1.65–2.00% |
| Chromium (Cr) | 0.70–0.90% |
| Molybdenum (Mo) | 0.20–0.30% |
| Phosphorus (P) | ≤ 0.035%* |
| Sulfur (S) | ≤ 0.040%* |
*Common published bar-grade maximums for phosphorus and sulfur. The exact contract edition and heat-analysis certificate govern acceptance; tighter restrictions may be specified.
Nickel, chromium and molybdenum support hardenability in 4340, making it a purchasing option for larger cross-sections and demanding mechanical loads.
Specify the actual annealed, normalized or quenched-and-tempered condition needed for your component. An agreed strength class and section size determine acceptance.
| Bar Diameter | Tensile Range | 0.2% Proof Stress |
|---|---|---|
| ≤ 60 mm | 1,000–1,150 MPa | ≥ 835 MPa |
| >60–100 mm | 930–1,080 MPa | ≥ 740 MPa |
| >100–178 mm | 930–1,080 MPa | ≥ 720 MPa |
| >178–240 mm | 900–1,000 MPa | ≥ 690 MPa |
These are published supplier examples for its specific Q&T material conditions, shown for procurement planning. Your specified bar size, ASTM strength class and mill test certificate establish the acceptance requirements.
Provide your downstream heat-treatment plan or requested final material condition when you enquire.
Bar stock for machining, forging and subsequent heat treatment. Quote by grade, diameter, length and ordered finish.
Specify annealed delivery when it suits your cut blanks and machining route. Agree hardness and dimensional acceptance.
Define the required mechanical property class, section size, hardness and inspection documentation in your purchase order.
Compare alloy families before preparing your material schedule. Each grade follows its own chemistry, delivery standards and agreed mechanical properties.
4340 includes approximately 1.65–2.00% nickel plus chromium and molybdenum. Its chemistry is often selected for larger or more heavily loaded sections.
4140 and 42CrMo are chromium-molybdenum grades used in machined components. Compare the actual project requirements and materials documentation before selecting a grade.
Related alloy grades are alternative purchasing subjects; final selection follows engineering approval and the specified material standard.
Plan your 4340 bar procurement with a steel manufacturer backed by production scale, company-wide inventory and quotation-based supply coordination.
Our actual annual steel production across product categories supports repeat and project procurement.
Manufacturing ↗Company-wide inventory supports supply coordination. Your specific 4340 bar diameter and condition are checked with each RFQ.
Inventory ↗Include the heat analysis, hardness, strength class, dimensions and inspection scope on your purchase schedule.
Quality Control ↗Send bar sizes, quantity, heat-treatment condition and the receiving port to obtain an order-specific offer.
Contact Sales ↗4340 is selected for demanding shafts, drive parts and machined assemblies where alloy hardenability and heat-treated properties matter.
Machine and drive shafts manufactured to defined strength and toughness requirements.
Gear blanks and pinions with size-specific machining and Q&T needs.
Loaded rotating components specified by diameter, condition and drawings.
Machined drive components using solid alloy steel bar stock.
Structural and mechanical parts for material-handling and production equipment.
Bar feedstock for parts requiring forging and subsequent heat treatment.
Estimate material mass from the solid round bar diameter, individual length and piece count before requesting freight terms.
Theoretical estimate using density 7,850 kg/m³. Final commercial weight depends on the actual diameter and delivery terms.
Provide the same information used by your production or sourcing team for a practical quotation.
Our steel business produces 8 million metric tons annually across product categories. Share your 4340 bar dimensions and condition requirements for a stock or production feasibility review.
Submit your requested bar diameter, condition, length and tonnage. Our team will confirm available supply routes, applicable lead times and delivery terms for your order.
Include the requested heat analysis, mechanical acceptance, diameter checks and certification in your steel bar purchase schedule.
Include cut blanks and drawing requirements with your bar enquiry. Confirm available preparation options, machining allowances and material condition together with your quotation.
Specify your required packing, bundle weights, bar lengths and destination. Our team can confirm loading and shipping arrangements for the quoted order.
Review other grades against the engineering specification for your machined component.
AISI / SAE 4340 is a nickel-chromium-molybdenum alloy steel with typical ranges of 1.65–2.00% Ni, 0.70–0.90% Cr, 0.20–0.30% Mo and 0.38–0.43% carbon.
State hot-wrought, annealed, normalized or quenched-and-tempered supply and any required hardness or mechanical strength. The applicable supply route is confirmed against size and specifications.
Send solid round bar diameter, length, quantity, surface condition, required test documents and destination port.
Use the nominal circular area and bar length with density 7,850 kg/m³. The calculator estimates weight per bar and total metric tons.
Send your required grade, dimensions, quantity and destination. Our team will review the inquiry.