What is 8740 Steel? An Introduction to Its Composition and Characteristics

8740 steel is a nickel-chromium-molybdenum alloy steel valued for its exceptional hardenability, strength, and toughness. With its balanced composition, 8740 round bar stock offers reliable performance in applications that demand durability and resistance to wear, making it a preferred choice across multiple industries.

Chemical Composition of 8740 Alloy Steel

The properties of 8740 steel are derived from its carefully balanced alloying elements:

Carbon: 0.38 – 0.43%
Manganese: 0.75 – 1.00%
Phosphorus: 0.035% max
Sulfur: 0.040% max
Silicon: 0.20 – 0.35%
Nickel: 0.40 – 0.70%
Chromium: 0.80 – 1.10%
Molybdenum: 0.15 – 0.25%

This combination provides excellent toughness, wear resistance, and heat-treating response, making 8740 steel ideal for high-stress environments.

Forging and Heat Treatment

8740 steel is typically forged between 2200°F (1205°C) and 1700°F (925°C). Its hardenability allows for quenching and tempering to achieve a wide range of strength and ductility levels, depending on application requirements.

Applications of 8740 Round Bar

Mozaic Precision Metals supplies 8740 steel bar stock for industries that require reliable, high-performance materials. Common uses include:

High-strength fasteners and bolts
Forged automotive and aerospace components
Oil and gas drilling equipment
Heavy-duty machinery parts
Wear-resistant industrial components

With its superior toughness, uniform hardenability, and versatile applications, 8740 round bar remains a trusted alloy for manufacturers demanding durability and long-lasting performance.

Contact the Best 8740 Alloy Steel Suppliers

Mozaic Precision Metals provides 8740 alloy steel round bar stock engineered for exceptional strength, toughness, and reliability. This chromium-nickel-molybdenum alloy offers superior hardenability and weldability, making it an ideal choice for applications that demand performance beyond the capabilities of standard carbon steel. With decades of expertise, we deliver high-quality metals that help businesses and manufacturers stay competitive and productive.

Why Choose 8740 Alloy Steel?

8740 alloy steel is known for its outstanding balance of strength, toughness, and durability. Its alloying elements and thermal treatments enhance performance, ensuring it can withstand extreme stress, fatigue, and demanding environments. Whether used in fasteners, structural components, or aerospace hardware, 8740 alloy steel delivers consistent results you can rely on.

Applications of 8740 Alloy Steel

High-Strength Fasteners – Ideal for bolts, screws, and nuts used in automotive, aerospace, and construction industries.

Automotive Components – Commonly used in gears, axles, and drive shafts where high stress and impact resistance are required.

Aerospace Industry – Applied in aircraft engine components, landing gear, and structural supports that require superior strength and reliability.

Construction & Heavy Machinery – Trusted for critical parts that must withstand high loads and challenging environments.

Dependable Supply from Mozaic Precision Metals

Our leadership team has over 60 years of combined experience in alloy steel supply and precision grinding. At Mozaic Precision Metals, we are committed to providing customers with top-quality 8740 alloy steel round bar stock tailored to their specific needs. Whether your project calls for bulk orders or custom specifications, you can count on us to deliver materials that perform.

Request a Quote Today: Contact Mozaic Precision Metals to secure high-quality 8740 alloy steel bar stock for your next project. We’ll provide the durability, strength, and reliability you need to get the job done right.