4140 Bar

4140 Bar and 4142 alloys are used in various industrial applications.

4140 Round Bar

4140 is a Chromium-Molybdenum alloy steel that is one of the most commonly used alloy steels.

Thus, the primary alloying elements are chromium and molybdenum. As a result, 4140 is used in applications that require high wear resistance and high temperatures. Meanwhile, 4142 alloys are used in various industrial applications, including tools and other types of equipment. After heat treatment, it is a medium carbon chromium-molybdenum alloy steel with high strength and toughness.  

O'Hare 4142 Steel Round Bar Stock

O’Hare Precision Metals can provide a wide range of company-supplied or customer-supplied components and materials. Just like how we can offer you the best 4140/4142 Alloys bar stocks and 4140/4142 Alloys round bar stocks in O’Hare!

Machinability and other Processes

4140 has a machinability rating of 66 percent, which is excellent. However, the presence of molybdenum contributes to the uniformity of hardness and high strength. Also, it is a complicated metal to weld, but it is possible if the section is preheated before welding and then stress relieved after welding.

4142 Alloy Steel and 4140 round stock is a through-hardening alloy steel with high strength and toughness after heat treatment. It possesses excellent fatigue and impact resistance. Alloy steels with tensile and yield strengths in 4140/4142 and 4140 round stock are available. The machinability of steel increases as it is hardened and tempered.


Axles, shafts, tools bodies, tie rods, stubs, couplings, reamers, gears, racks are the common applications of 4140/4142 Alloys.



Poisson’s ratio 

Elastic modulus

Bulk modulus 

Shear modulus 

0.284 lb/in³  


27557-30458 ksi  

20300 ksi   

11600 ksi

Chemical Properties









0.40-0.45 0.380 – 0.430

0.80-1.10 0.80 – 1.10

0.75-1.10 0.75 – 1.0

0.15-0.25 0.15 – 0.25

 0.035 0.035

0.15-0.30 0.15 – 0.30

0.040 0.040

96.725 Balance

4140 Bar Stock VS 4142 Steel

4140 Steel Bar Stock

The 4140 bars are used in a variety of applications, including automotive and aerospace industries. In the Automotive industry: the 4140 bar is often used as an automotive part because it can be forged into any shape, size, or thickness that the customer needs. In this way, it can be customized to fit the specific needs of the company’s product design.

It is usually a steel bar that has been heat-treated and quenched. It is an alloy of chrome, nickel, and molybdenum. 4140 bar stock is a type of steel that is used for making bars for the manufacturing industry.

4140 bar has a higher tensile strength than other types of steel in the same class. This makes it a popular choice for when you need to make bars that are going to be used in high-stress situations like machinery or automobiles.

4140 bar stock doesn’t rust as easily as other types of steel because it has been heat-treated and quenched, which removes all traces of impurities from the metal.

4140 bar is a type of steel that has a low carbon content and is known for its strength and toughness. It is an alloy steel that has a high nickel content, which gives it better resistance to corrosion than other types of steel.

The main advantage of 4140 bar is its ability to be heat-treated to very high strengths, with good ductility. It can be easily machined, welded, drilled, and tapped. This makes it popular for use in structural applications such as I-beams.

4142 Steel  

4142 steel is a material that is used in the production of automobiles, construction equipment, and other machinery. It is a specification for alloy steel containing nickel, chromium, molybdenum, and columbium. Plus, 4142 alloy steel has good corrosion resistance and can be used in many different applications.

4142 alloy steel is a type of steel that is used in many industries. It has good corrosion resistance, strength, and toughness properties.

Also, 4142 alloy steel is a low carbon, high nickel, and high chromium steel. It has excellent formability and weldability in annealed conditions. When compared to other similar materials like 4130 or 4140, it has a lower carbon content which makes it easier to machine. This also means that 4142 steel doesn’t require as much heat during welding because of its lower melting temperature.

O’Hare’s 4140 Bar and 4140 Steel for Sale

O’Hare Precision Metals is a company that specializes in the sale of 4140 bar stock and 4142 alloy steel. We are a leading provider of these materials in the United States. We offer all kinds of metals and metal products that are quality fit for your high demands.

Want to know more about 4140/4142 Alloys? Just contact our highly skilled personnel in O’Hare Precision Metals. They are dedicated to providing smooth-flow service. Request a quote for 4140/4142 Alloys bar stocks now!