4140 Tool Steel Grade Shapes, Sizes, and Technical Information From Tool Steel Service Inc.

AISI 4140 is an alloy steel that is supplied in either annealed or prehardened condition. The alloy steel is composed of chromium, molybdenum, manganese containing low alloy steel. It is characterized by its high fatigue strength, torsional strength, abrasion resistance, toughness. The prehardened condition is heated to medium hardness (HRC 26/34) plate to be used as a holder material for high strength structural components. 

4140 Tool Steel Shapes and Sizes

4140 tool steel is available in the following thickness sizes and standard width sizes depicted in the tables below. Any non-standard thickness and width is available upon request.

Thickness Sizes*
1/4 1-3/4
3/8 2
1/2 2-1/4
5/8 2-1/2
3/4 2-3/4
7/8 3
1 3-1/2
1-1/8 4
1-1/4 4-1/2
1-3/8 5
1-1/2 6

*Non-standard thickness available upon request.

Standard Width Sizes**
1 7
1-1/2 8
2 10
2-1/2 12
3 14
3-1/2 16
4 18
5 24

**We will also cut any width required.

4140 Tool Steel Grade Technical Specifications

Typical Analysis of 4140 Tool Steel

4140 Prehard Alloy
Chemical Composition %
Carbon (Max.) .38/.46
Manganese .70/1.00
Phosphorus (Max.) .35
Sulfur (Max.) .040
Chromium .80/1.15
Molybdenum .15/.25
Silicon .15/.40
Vanadium .03
Other Elements  
Heat Treatment Required N&T
Surface Brinell Hardness (HB) 262/321 to 3" incl.; 241/321 over 3" to 6-1/2" incl.

General Characteristics of 4140 Tool Steel

General Characteristics

AISI 4140 grade is a low-alloy steel that contains chromium and molybdenum that act as a strengthening agent.  It is a versatile alloy steel that has a good combination of strength, toughness, corrosion resistance, and wear resistance.

Typical applications of 4140 Tool Steel

Typical Applications

4140 is the most commonly used of the high tensile steels with a wide range of
applications in automotive, Gear and Engine construction, Crankshafts, Steering
knuckles, Connecting rods, Spindles, Intermediate gears, Pump and Gear shafts.
Axles, Nuts and Bolts. 

4140 Tool Steel Inventory

4140 Precision Ground Flat Stock Standard Tolerance
4140 HT Decarb Free Plate

Check our stock of the 4140 Tool Steel Grade

Order 4140 Tool Steel today

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