High-Strength Chromium-Molybdenum Alloy Plates | EN10083-3 / ASTM A29 / A322 Standards

AISI 4140 Alloy Steel Plate Overview

AISI 4140 Alloy Steel Plate, also known as 42CrMo4 steel, is one of the most widely used chromium-molybdenum alloy steels, valued for its high strength, toughness, and excellent hardenability. It is supplied under multiple international standards such as ASTM A29 / A322 (4140), SAE 4140, and EN 42CrMo4, making it a highly versatile engineering material.

In addition to 4140 alloy steel, related grades such as AISI 4135, AISI 4142, and AISI 6150 are also available, each providing specific mechanical advantages for heavy-duty components.

For a deeper breakdown of 4140 steel, see our related blogs:

🔗4140 Steel Technical Guide: Properties, Composition and Equivalents

🔗4140 Steel: Properties, Applications & Heat Treatment Guide

Product Parameters

Product Name	4135/4140/4142/6150 Alloy Plate EN10083-3
Production Process	Hot Rolling, Cold Rolling
Material Standards	AISI, ASTM, ASME, DIN, BS, EN, ISO, JIS, GOST, SAE, etc.
Width	100mm-3000mm
Length	1m-12m, or Customized Size
Thickness	0.1mm-400mm
Delivery Conditions	Rolling, Annealing, Quenching, Tempered or Standard
Surface Process	Ordinary, Wire Drawing, Laminated Film

Chemical Composition

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

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

💡 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.
• AISI 6150 is a popular choice for high-load automotive and machinery parts, and we offer wholesale 6150 alloy plate at competitive export pricing. For bulk orders or customized 6150 cold drawn profiles, please contact our sales team for a fair quotation based on your specifications.

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.

👉 See our AISI 4140 Alloy Steel Bar page for round and forged bar options.

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