High-Strength AISI 4140 Alloy Steel Plate | ASTM A29 / A322 & EN 42CrMo4

AISI 4140 Alloy Steel Plate Overview

AISI 4140 alloy steel plate is widely supplied for heavy-duty mechanical and structural applications requiring high strength and toughness. We provide export-ready 4140 steel plates in annealed or quenched & tempered condition, with custom cutting, machining, and fast delivery for global buyers.

This chromium-molybdenum alloy steel is commonly used for shafts, gears, and high-load components, and is supplied according to ASTM A29 / A322 and EN 42CrMo4 standards to meet international project requirements.

Product Parameters – AISI 4140 Alloy Steel Plate Supply Range

Item	Specification
Product Name	AISI 4140 Alloy Steel Plate
Production Process	Hot Rolled (HR), Forged Plate
Material Standards	ASTM A29 / A322 (4140), SAE 4140, EN 42CrMo4, DIN 1.7225
Thickness	6 mm – 400 mm
Width	100 mm – 3000 mm
Length	1 m – 12 m, or Custom Cut-to-Length
Heat Treatment Condition	Annealed, Normalized, Quenched & Tempered (Q&T)
Surface Condition	Black, Machined, Ground, Anti-Rust Coated
Tolerance	As per ASTM / EN standards or customized
MOQ	1 ton (negotiable for trial orders)
Delivery Time	7–25 days depending on size and quantity

AISI 4140 Alloy Steel Plate Supply & Export Services

Stock & Availability

• Regular sizes available in stock for fast dispatch
• Support both standard plates and custom specifications

Processing Services

• Cut-to-length, flame cutting, and CNC machining available
• Surface grinding and rough machining supported

Heat Treatment Options

• Supplied in annealed or quenched & tempered condition
• Customized heat treatment based on application requirements

Export & Packaging

• Export-grade packing (wooden pallets / seaworthy packing)
• Full documentation including MTC (Mill Test Certificate)

Delivery & Logistics

• Typical lead time: 7–25 days
• Container shipment and bulk order support

Learn more about 4140 steel applications and heat treatment processes in our 4140 steel applications and heat treatment guide.

Typical Applications of 4140 Alloy Steel Plate

4140 steel plate is widely used across industries including:

• Heavy machinery: shafts, gears, couplings, high-strength fasteners
• Automotive & transport: crankshafts, transmission components
• Energy & oilfield: drill collars, pressure-bearing parts
• General engineering: forged parts, structural components

Chemical Composition of 4140 and Related Alloy Steel Grades

The following data is provided for technical reference and grade comparison during material selection.

Brand	C	Si max	Mn	P max	S max	Cr	Mo	V	Key Features
AISI 4135 / 34CrMo4	0.3-0.37	0.40	0.6-0.9	0.025	0.035	0.9-1.2	0.15-0.3	–	Good machinability, balanced strength
AISI 4140 / 42CrMo4	0.38-0.45	0.40	0.6-0.9	0.025	0.035	0.9-1.2	0.15-0.3	–	High tensile strength, versatile performance
AISI 4142 / 50CrMo4	0.46-0.54	0.40	0.5-0.8	0.025	0.035	0.9-1.2	0.15-0.3	–	Higher hardness, better wear resistance
AISI 6150 / 51CrV4	0.47-0.55	0.40	0.7-1.1	0.025	0.025	0.9-1.2	–	0.1-0.25	Excellent fatigue strength, Cr-V alloy

Mechanical Properties of Alloy Steel Plates

Grade	Thickness (mm)	Yield Strength (MPa)	Tensile Strength (MPa)	Elongation (%)	Reduction of Area (%)	Impact Energy KV2 (J)	Typical Applications
AISI 4135	≤ 80	850	950–1150	16	45–60	40–70	Shafts, gears, axles with higher machinability
AISI 4140	≤ 80	900	1000–1300	14	40–60	35–70	Crankshafts, coupling rods, heavy-duty fasteners
AISI 4142	≤ 80	950	1050–1350	13	35–55	30–60	Dies, molds, wear-resistant parts
AISI 6150	≤ 80	850	1100–1300	13	40–55	45–65	Springs, torsion bars, mechanical components under fatigue
All Grades (100–160 mm)	100–160	800–850	950–1200	12	30–50	25–55	Forged, machined, or structural parts

For most industrial applications, AISI 4140 alloy steel plate remains the preferred grade due to its balanced performance and stable supply availability.

For detailed technical background, please refer to 4140 steel mechanical properties and chemical composition guide.

Design & Procurement Insight

• AISI 4140 offers the best all-around performance and is the preferred choice for over 80% of industrial uses.
• AISI 4135 is more cost-effective where moderate strength and excellent machinability are required.
• AISI 4142 provides enhanced surface hardness after heat treatment, ideal for tooling or wear parts.
• 6150 alloy steel plate, strengthened by vanadium, is ideal for fatigue-critical components.

Based on current demand, we also support wholesale 6150 alloy plate supply and customized 6150 cold drawn profiles for export-oriented buyers seeking stable quality and competitive pricing.

Why Choose CJM as Your 4140 Alloy Steel Plate Supplier

✅ Certified Quality – Supplied with EN 10204 3.1 mill certificates, ensuring full traceability and quality compliance.
✅ Flexible Supply Condition – Available annealed for machining or quenched & tempered for direct use.
✅ Custom Processing – Precision cutting, grinding, and heat treatment available upon request.
✅ Stable Supply Chain – We maintain strategic 4140 plate stock, ensuring faster delivery and consistency for both standard and special grades.

Looking for bar products? Visit our AISI 4140 Alloy Steel Bar page for round and forged bar options.

Packaging & Export Delivery

4140 alloy steel plate is securely packed for export using steel strapping, wooden pallets, and moisture protection to ensure safe international transportation.

Request a Quote – 4140 Alloy Steel Plate

Looking for a fair price on 4140 alloy steel plate or 6150 alloy plate?

Contact CJM Steel today for a competitive quotation with certified quality, reliable delivery, and professional export support.
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Q: What is your company’s main products/services?

A: We are a professional manufacturer for Carbon Steel, Alloy Steel and Profile products. We have the experience of steel business for more than 10 years and our products are exported to Mid East,South America,Southeast Asia,Africa,South and East Asia etc.

Q: Can I go to your factory for a visit?

A: Of course, we welcome customers from all over the world to visit our factory.

Q: What are your terms of payment?

A: 30% T/T deposite and 70% balance before shipment.

Q: What is your delivery time?

A: For stocks,we could transport the goods to loading port within 7 days after we received the deposit; For production,it usually takes about 15-30 days after receiving the deposit.

Q: Do you provide samples? Are they free or paid?

A: Samples are available for free,but the courier freight will be covered by customer account.

Q: Do you accept the third party inspection?

A:Yes, we fully accept ‌third-party inspections.

Q: Why should I buy from you not from other suppliers?

A: Integrating the superior resources of China’s steel industry, we provide customers with high-quality steel products at preferential prices, and can ensure that the goods are delivered to customers in a timely manner.

Q:How can you guarantee quality?

A: Always a pre-production sample before mass production;Always 100% inspected before shipment