What is EN 351 Case Hardening Steel Round Bar?
EN 351 Case Hardening Steel Round Bar is a low carbon alloy steel specifically developed for case hardening applications. This grade contains alloying elements such as chromium, nickel, and molybdenum that improve strength, toughness, and wear resistance after heat treatment. The steel is commonly used for manufacturing machine components that require a hard outer surface with a tough inner core.
Due to its excellent metallurgical properties, EN 351 Case Hardening Steel Round Bar is widely used in automotive, machinery, and engineering industries. The steel is suitable for carburizing processes that create a hardened surface layer while maintaining ductility and toughness in the core. The product is available in Bright and Black Conditions and supplied with proper test certification. Standard sizes generally range from 10 mm to 280 mm in diameter, with standard lengths of 3 meter to 6 meters, although customized lengths can also be supplied according to specific application requirements.
Chemical Composition of EN 351 Case Hardening Steel Round Bar
The chemical composition of EN 351 Case Hardening Steel Round Bar provides a combination of hardness, strength, and toughness after heat treatment.
| Element | Content (%) |
|---|---|
| Carbon (C) | 0.20 Max |
| Silicon (Si) | 0.10 –0.35 |
| Manganese (Mn) | 0.60–1.00 |
| Phosphorus (P) | 0.015 Max |
| Sulphur (S) | 0.030 Max |
| Chromium (Cr) | 0.40–0.80 |
| Molybdenum (Mo) | 0.10 Max |
| Nickel (Ni) | 0.60 –1.00 |
The presence of alloying elements such as chromium, molybdenum, and nickel improves hardenability, strength, and wear resistance, making this steel suitable for demanding engineering applications.
Equivalent Grades of EN 351 Case Hardening Steel Round Bar
EN 351 is recognized internationally and has equivalent grades in several global standards:
| Standard | Equivalent Grade |
|---|---|
| BS 970:1991 | 655M13 |
| BS 970 | EN351 |
| AISI / SAE | 3310 |
| DIN | 20NiCrMo2-2 |
These equivalent grades help maintain similar chemical composition and mechanical properties, enabling global sourcing and compatibility with international specifications.
Applications of EN 351 Case Hardening Steel Round Bar
Due to its superior strength and surface hardening capability, EN 351 Case Hardening Steel Round Bar is widely used in several industrial applications.
- Automotive gears and transmission components
- Shafts, pinions, and gear blanks
- Machine components requiring wear resistance
- Heavy duty engineering parts
- Industrial gears and drive components
The round bar shape ensures uniform stress distribution, making it ideal for rotating components and precision machined parts.
Availability and Customization
EN 351 Case Hardening Steel Round Bars are available in a wide range of diameters from 10 mm to 280 mm. Standard bar lengths range from 3 meter to 6 meters, although customized lengths can be supplied according to project requirements.
Custom manufacturing helps reduce material wastage and improves production efficiency for engineering industries. Bars are available in black, bright, and heat treated conditions depending on the specific application.
Industry Applications
Engineering Industry
EN 351 Case Hardening Steel Round Bars are widely used in engineering industries for manufacturing gears, shafts, and high-strength mechanical components. The steel offers good machinability in the annealed condition and develops excellent hardness after case hardening. These properties make it suitable for heavy duty engineering applications where durability and wear resistance are required.
Automobile Industry
The automotive sector uses EN 351 Case Hardening Steel Round Bar for producing gears, transmission shafts, pinions, and axle components. The grade provides high surface hardness after carburizing while maintaining a tough and impact-resistant core. These characteristics are essential for automotive components that operate under cyclic loads and high stresses.
Machinery Manufacturing Industry
Machinery manufacturers rely on EN 351 Case Hardening Steel Round Bar for producing machine parts such as gears, camshafts, and mechanical drive components. The steel grade offers good machinability before heat treatment and excellent hardness and wear resistance after case hardening. This combination makes it highly suitable for long-lasting industrial machinery parts.
Key Features of EN 351 Case Hardening Steel Round Bar
- Excellent case hardening capability
- High wear resistance after heat treatment
- Tough and ductile core for impact resistance
- Good machinability in annealed condition
- Reliable performance under heavy mechanical loads
Why Choose STEEL MART for EN 351 Case Hardening Steel Round Bar?
STEEL MART is a trusted supplier of EN 351 Case Hardening Steel Round Bar with decades of experience in the steel industry. Our commitment to quality, strict quality control processes, and advanced manufacturing practices allow us to deliver steel products that meet international standards.
With over 40 years of experience, STEEL MART has built a strong reputation for supplying high-quality steel products with minimum rejection rates and competitive prices. Our EN 351 Case Hardening Steel Round Bar is widely appreciated for its durability, performance, and consistent quality. Many of our clients continue to place repeat orders due to our reliability and commitment to customer satisfaction.
Conclusion
EN 351 Case Hardening Steel Round Bar is a premium alloy steel grade designed for applications requiring a hard wear-resistant surface combined with a tough core. Its excellent hardenability, strength, and durability make it suitable for manufacturing gears, shafts, pinions, and other heavy duty engineering components. With proper heat treatment, the material provides superior wear resistance and long service life.
STEEL MART supplies EN 351 Case Hardening Steel Round Bar in a wide range of sizes and conditions, ensuring high quality and reliability for engineering, automotive, and machinery manufacturing industries.
FAQs
(1)What is EN 351 Case Hardening Steel Round Bar mainly used for?
It is mainly used for gears, shafts, pinions, and machine components that require a hard wear-resistant surface.
(2)Can EN 351 steel be case hardened?
Yes, EN 351 is specifically designed for case hardening processes such as carburizing to achieve a hard outer surface.
(3)Do you supply EN 351 Round Bars with a test certificate?
Yes, EN 351 Case Hardening Steel Round Bars are supplied with a proper mill test certificate.
(4)What are the available sizes of EN 351 Round Bars?
The bars are available in diameters from 10 mm to 280 mm and standard lengths from 3 m to 6 m.
(5)Is EN 351 steel suitable for automotive components?
Yes, it is widely used in the automotive industry for gears, transmission parts, and other high-strength components.
