Polished Surface 4340 Alloy Steel Round Bar with Custom Cutting for Mold Steel Applications
Price:
US $968-1,155 / Ton
MOQ:
1 Ton
Delivery Time:
Negotiable
Product Description
Grade 4340 / 40CrNi2Mo / 40CrNiMoA Alloy Steel Round Bar
Diameter Range: 30 - 300mm
Standard Length: 6 meters
Material Grade: 4340 Alloy Steel
Custom Cutting: Available
Product Specifications
| Parameter | Specification |
|---|---|
| Diameter | 13 - 300mm |
| Length | 6m or custom cutting as requested |
| Grade | 4340 Alloy Steel |
| Services | Cutting, polishing, packing, heat treatment |
| Brands | BAOSTEEL, XINGCHENG, DSS, CHONGQING, XNSS, HLXT, etc. |
| Standards | GB, ASTM, JIS, EN, DIN |
| Company Type | Storage company and processing service |
Material Overview
AISI 4340 steel (UNS G43400) is an ultra-high strength medium carbon low alloy steel that combines deep hardenability, high ductility, toughness, and strength. It features high fatigue resistance and creep resistance, with minimal impact from tempering and embrittlement. This steel maintains good strength retention at high temperatures and resists softening. In thin sections, it is air-hardened, though oil quenching is typically used in practice.
Chemical Composition
| ASTM Standard | Steel Grade (UNS) | C | Si | Mn | P (≤) | S (≤) | Ni | Cr | Mo | Notes |
|---|---|---|---|---|---|---|---|---|---|---|
| ASTM A29/A29M | 4340 alloy steel (UNS G43400) | 0.38-0.43 | 0.15-0.35 | 0.60-0.80 | 0.035 | 0.04 | 1.65-2.00 | 0.70-0.90 | 0.20-0.30 | Steel Bars, Carbon and Alloy, Hot-Wrought |
Mechanical Properties
| Condition | Tensile Strength, MPa (ksi), ≥ | Yield Strength, MPa (ksi), ≥ | Elongation in 50 mm (2 in.), ≥ | Reduction in Area, %, ≥ | Hardness, HB, ≤ |
|---|---|---|---|---|---|
| Normalized at 870 °C (1600 °F) | 1282 (186) | 862 (125) | 12.2 | 36.3 | 363 |
| Annealed at 810 °C (1490 °F) | 745 (108) | 470 (68) | 22.0 | 50.0 | 217 |
| Oil quenched from 800 °C (1475 °F) and tempered at 540 °C (1000 °F) | 1207 (175) | 1145 (166) | 14.2 | 45.9 | 352 |
Applications
SAE AISI 4340 steel is ideal for applications requiring high strength under severe conditions and heavy loads. It is widely used as billet, bar, forging, sheet, pipe, and welding wire, and can also be produced as light plates and castings.
- Bolts, screws, and other fasteners
- Gears, pinions, shafts, and similar mechanical components
- Crankshafts and piston rods of engines
- Landing gear and other key structural components of aircraft
International Equivalents
| Region | Standard | Grade |
|---|---|---|
| USA | AISI, SAE, ASTM A29/A29M, ASTM A322, ASTM A519/A519M, ASTM A646/A646M | 4340 (UNS G43400) |
| China | GB/T 3077 | 40CrNi2Mo |
| Japan | JIS G 4053 | SNCM439 |
Company Capabilities
We maintain strategic partnerships with major steel mills including Ling Steel, Xuan Steel, Benshan Steel, Tiangang, Shandong Luli Steel, Rongcheng Steel, Professional, Handan, Laigang, and Jiyuan Steel. Our monthly sales volume ranges from 40,000 to 60,000 tons of various steel types.
Warehouse & Processing Facilities:
- 4+ warehouses for stock management
- 30+ product grades consistently in stock
- 800+ sizes available for quick delivery
- Dedicated processing warehouse for cutting, polishing, and heat treatment
Our products serve various industries including machinery, standard parts, automotive, gears, forging, and hardware tools, with a global sales network.
Available Steel Grades
We manufacture and supply a comprehensive range of steel grades including EN series (EN19, EN24, EN25, EN26, EN30, EN31, EN36C, EN39, EN40, EN41B, EN42, EN9, EN14A, EN15, EN16, EN18, EN47, EN100, EN351, EN353, EN354, EN355), C series (C22E, C25E, C30, C35E, C45, CK45, C50, C55, C60), S series (S45C, S235J2, S275J2, S355J2, ST52.3), and numerous specialized alloys meeting ASTM, DIN, GOST, and other international standards.
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Company
JIANGSU MITTEL STEEL INDUSTRIAL LIMITED
Location
No.283-1, Youyi Middle Road, Xishan District, Wuxi City, Jiangsu Province
Contact Person
Gao Ben