Overview
Special Steel 8620/1.6523/20CrNiMoA/SNCM220 Alloy Steel is a highly versatile and widely used steel variant, known for its excellent properties in terms of hardenability, strength, and toughness. This alloy steel is particularly suitable for applications requiring high wear resistance and fatigue strength. It’s a low-carbon, low-alloy steel containing nickel, chromium, and molybdenum as its primary alloying elements. In this article, we will delve deep into the specifics of this special steel, covering its chemical composition, properties, applications, specifications, suppliers, and more. Let’s embark on this detailed exploration.
Chemical Composition of Special Steel 8620/1.6523/20CrNiMoA/SNCM220 Alloy Steel
Understanding the chemical composition of this alloy steel is crucial as it directly influences its mechanical properties and suitability for various applications.
| Element | Content (%) |
|---|---|
| Carbon (C) | 0.18 – 0.23 |
| Silicon (Si) | 0.15 – 0.35 |
| Manganese (Mn) | 0.70 – 0.90 |
| Phosphorus (P) | ≤ 0.035 |
| Sulfur (S) | ≤ 0.035 |
| Chromium (Cr) | 0.40 – 0.60 |
| Nickel (Ni) | 0.40 – 0.70 |
| Molybdenum (Mo) | 0.15 – 0.25 |
Properties and Characteristics of Special Steel 8620/1.6523/20CrNiMoA/SNCM220 Alloy Steel
This alloy steel’s properties make it highly desirable for various demanding applications.
| Property | Description |
|---|---|
| Hardenability | Good, can be carburized |
| Toughness | High, even at low temperatures |
| Wear Resistance | Excellent, due to its hard surface layer after heat treatment |
| Fatigue Strength | Superior, suitable for cyclic loading applications |
| Machinability | Good, easy to machine in both annealed and hardened conditions |
| Weldability | Fair, can be welded with proper precautions |
Mechanical Properties of Special Steel 8620/1.6523/20CrNiMoA/SNCM220 Alloy Steel
| Property | Value |
|---|---|
| Tensile Strength | 800 – 1100 MPa |
| Yield Strength | 400 – 650 MPa |
| Elongation | 12 – 18% |
| Hardness (HRC) | 28 – 34 |
| Impact Strength | High, suitable for high-stress applications |
Applications of Special Steel 8620/1.6523/20CrNiMoA/SNCM220 Alloy Steel
The versatility of this steel makes it suitable for a broad range of applications.
| Application | Details |
|---|---|
| Automotive Components | Used in gears, crankshafts, and connecting rods due to high fatigue strength |
| Industrial Machinery | Ideal for manufacturing machine parts that require high wear resistance |
| Aerospace | Suitable for producing components that must withstand high stress and temperature |
| Tooling | Used in the production of dies and molds due to its good machinability and hardness |
| Oil and Gas Industry | Employed in drill collars and other downhole tools due to its toughness and wear resistance |
Specifications of Special Steel 8620/1.6523/20CrNiMoA/SNCM220 Alloy Steel
| Specification | Details |
|---|---|
| Standard | ASTM A29, ASTM A322, JIS G4053 |
| Grade | 8620, 1.6523, 20CrNiMoA, SNCM220 |
| Sizes | Available in rounds, squares, flats, and hexagonal bars |
| Heat Treatment | Can be annealed, normalized, or carburized |
Standards and Grades
| Standard | Grade |
|---|---|
| ASTM | 8620 |
| DIN | 1.6523 |
| JIS | SNCM220 |
| GB | 20CrNiMoA |
Suppliers and Pricing of Special Steel 8620/1.6523/20CrNiMoA/SNCM220 Alloy Steel
Finding reliable suppliers and understanding pricing is essential for procurement.
| Supplier | Location | Price Range (per kg) |
|---|---|---|
| ABC Steel Corp | USA | $2.00 – $2.50 |
| XYZ Metals Ltd | Germany | €1.80 – €2.20 |
| Shanghai Steel | China | ¥15 – ¥20 |
| Global Alloys | UK | £1.50 – £2.00 |
Advantages and Limitations of Special Steel 8620/1.6523/20CrNiMoA/SNCM220 Alloy Steel
Advantages
- Versatility: Suitable for a wide range of applications.
- High Strength and Toughness: Makes it ideal for demanding applications.
- Good Wear Resistance: Extends the life of components.
- Excellent Hardenability: Ensures a hard surface layer post heat treatment.
Limitations
- Cost: More expensive than some other steels due to its alloying elements.
- Weldability: Requires careful welding practices to avoid cracking.
- Availability: May not be readily available in all regions, leading to longer lead times.
Comparison with Other Alloy Steels
| Feature | 8620/1.6523/20CrNiMoA/SNCM220 | 4140 | 4340 |
|---|---|---|---|
| Hardenability | Good | Very Good | Excellent |
| Wear Resistance | Excellent | Good | Very Good |
| Toughness | High | Moderate | High |
| Cost | Higher | Moderate | Higher |
| Machinability | Good | Good | Moderate |
Heat Treatment of Special Steel 8620/1.6523/20CrNiMoA/SNCM220 Alloy Steel
Heat treatment is a critical process that enhances the mechanical properties of this alloy steel.
Carburizing Process
- Objective: To increase surface hardness while maintaining a tough core.
- Procedure:
- Heating: Heat the steel to 900-950°C.
- Carburizing: Maintain at this temperature in a carbon-rich environment.
- Quenching: Rapid cooling in oil or water to harden the surface.
- Tempering: Reheating to 150-200°C to reduce brittleness.
Annealing Process
- Objective: To soften the steel for improved machinability.
- Procedure:
- Heating: Heat to 820-850°C.
- Holding: Maintain at this temperature for a suitable duration.
- Cooling: Slow cooling in the furnace.
Comparative Analysis: Special Steel 8620 vs. Other Steels
Special Steel 8620 vs. 4140 Alloy Steel
| Feature | 8620 Alloy Steel | 4140 Alloy Steel |
|---|---|---|
| Hardenability | Good | Very Good |
| Wear Resistance | Excellent | Good |
| Toughness | High | Moderate |
| Machinability | Good | Good |
| Cost | Higher | Moderate |
Special Steel 8620 vs. 4340 Alloy Steel
| Feature | 8620 Alloy Steel | 4340 Alloy Steel |
|---|---|---|
| Hardenability | Good | Excellent |
| Wear Resistance | Excellent | Very Good |
| Toughness | High | High |
| Machinability | Good | Moderate |
| Cost | Higher | Higher |
Selecting the Right Steel for Your Application
Choosing the right steel involves considering several factors including mechanical properties, cost, availability, and specific application requirements. Special Steel 8620/1.6523/20CrNiMoA/SNCM220 is an excellent choice for applications requiring a balance of toughness, wear resistance, and hardenability. However, for applications demanding higher strength and toughness, steels like 4340 may be more suitable despite the higher cost.
Conclusion
Special Steel 8620/1.6523/20CrNiMoA/SNCM220 Alloy Steel is a highly versatile material that meets a wide range of industrial needs due to its superior mechanical properties. Whether you’re in the automotive, aerospace, or machinery industry, understanding its characteristics and applications can significantly enhance your project outcomes. This guide aims to provide you with comprehensive knowledge, enabling you to make informed decisions when selecting materials for your applications.
FAQs
| Question | Answer |
|---|---|
| What are the primary alloying elements in 8620 steel? | Nickel, Chromium, and Molybdenum. |
| Can 8620 steel be welded? | Yes, but it requires proper precautions to avoid cracking. |
| What is the typical hardness of 8620 steel after heat treatment? | Between 28 and 34 HRC. |
| Where is 8620 steel commonly used? | In automotive components, industrial machinery, and aerospace applications. |
