Polished Surface 4340 Alloy Steel Round Bar with Custom Cutting for Mold Steel Applications

最小注文数量	1トン
価格	US $968-1,155 / Ton

商品の詳細

直径範囲	30～300mm	長さ	6Mまたは注文
鋼種	4340 合金鋼	炭素含有量	0.38～0.43%
シリコン含有量	0.15～0.35%	マンガンの内容	0.60～0.80%
リン含有量	≤0.035%	硫黄分	≤0.04%
ニッケル含有量	1.65～2.00%	クロムの内容	0.70～0.90%
モリブデン含有量	0.20～0.30%	抗張力	1282 MPa (186 ksi)
降伏強さ	862 MPa (125 ksi)	伸長	12.2%
硬度	363HB
ハイライト	Polished Surface Alloy Steel Round Bar , Custom Cutting 4340 Steel Round Bar , Mold Steel Application 40CrNiMoA Steel Round Bar

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製品の説明

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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