Project Description
AISI 420, 1.4021 Martensitic Stainless Steel
Product Description
AISI 420, 1.4021 is a versatile martensitic stainless steel characterized by an excellent combination of strength, hardness, and moderate corrosion resistance. With a carefully balanced chemical composition featuring 12.0-14.0% chromium and 0.16-0.25% carbon, this grade offers superior hardenability and can achieve high hardness and strength through heat treatment. AISI 420 (1.4021) is distinguished from other martensitic stainless steels by its optimal carbon content, which provides excellent mechanical properties while maintaining good machinability and fabrication characteristics. This alloy delivers reliable performance in applications requiring wear resistance combined with moderate corrosion resistance, making it a preferred choice across multiple industries from cutlery manufacturing to industrial valve components.
Applications
AISI 420, 1.4021 martensitic stainless steel is specifically designed for applications requiring a combination of high strength, hardness, and moderate corrosion resistance. Its primary applications include:
- Cutlery and professional knife blades
- Surgical and dental instruments
- Valve components for oil and gas applications
- Pump shafts and impellers
- Fasteners and bolting for moderate corrosive environments
- Industrial machinery components
- Turbine blades for low-temperature service
- Plastic molds where corrosion resistance is required
- Steam and gas turbine blades and buckets
- Food processing equipment and shafts
- Ball bearings for non-extreme environments
- Shear blades for cutting applications
The excellent combination of mechanical properties and moderate corrosion resistance makes AISI 420, 1.4021 particularly valuable for applications where both wear resistance and the ability to withstand mildly corrosive environments are required.
Standards
AISI 420, 1.4021 martensitic stainless steel complies with the following international standards:
- American Standards: ASTM A276/A276M, ASTM A479/A479M, ASTM A582/A582M Type 420
- European Standards: EN 1.4021, EN 10088-3, X20Cr13
- ASME: SA-276 Type 420
- UNS: S42000
- British Standards: BS 970 420S29, 420S45
- German Standards: DIN 17440 X20Cr13
- Japanese Standards: JIS SUS 420J1, SUS 420J2
- Chinese Standards: GB/T 1220 2Cr13
- ISO: ISO 683-13 X20Cr13
Chemical Composition and Grade Comparison
Chemical Composition (in %)
| Element | C | Si | Mn | P | S | Cr | Ni |
|---|---|---|---|---|---|---|---|
| Min | 0.16 | ≤ | ≤ | ≤ | ≤ | 12.0 | ≤ |
| Max | 0.25 | 1.00 | 1.50 | 0.040 | 0.030 | 14.0 | 0.75 |
Grade Equivalents
| Standard | Designation |
|---|---|
| UNS | S42000 |
| EN/DIN | 1.4021, X20Cr13 |
| AISI/SAE | 420 |
| British | 420S29, 420S45 |
| Japanese | SUS 420J1, SUS 420J2 |
| Chinese | 2Cr13 |
Comparison with Similar Grades
| Property | AISI 420 (1.4021) | AISI 410 (1.4006) | AISI 431 (1.4057) |
|---|---|---|---|
| Carbon Content | 0.16-0.25% | 0.08-0.15% | 0.12-0.22% |
| Chromium Content | 12.0-14.0% | 11.5-13.5% | 15.0-17.0% |
| Typical Hardness (HRC) | Up to 50 | Up to 42 | Up to 52 |
| Corrosion Resistance | Moderate | Moderate | Good |
| Key Characteristic | Balanced properties | Better weldability | Better corrosion resistance |
Mechanical Properties
AISI 420, 1.4021 offers excellent mechanical properties in the quenched and tempered (QT) condition:
Mechanical Properties in Quenched and Tempered (QT) Condition
| Property | Value |
|---|---|
| Diameter OD range in mm (inch) | ≤ 380 (15) |
| 0.2%-Offset-Yield Strength Rp0.2 in MPa (ksi) | ≥ 517 (75) |
| Tensile Strength Rm in MPa (ksi) | ≥ 655 (95) |
| Elongation L0 = 4 d (A5) in % | ≥ 15 |
| Impact Toughness (Charpy-V at -10 °C) in J (ft-lbs) | ≥ 20 J (15) |
| Hardness in BHN (HRC) | ≥ 241 (22) |
Physical Properties
| Property | Value |
|---|---|
| Density | 7.8 g/cm³ at 20°C |
| Elastic modulus | 215 GPa at 20°C |
| Thermal conductivity at 20°C | 24.9 W/m·K |
| Specific heat capacity at 20°C | 460 J/kg·K |
| Electrical resistivity at 20°C | 0.55 μΩ·m |
| Thermal expansion coefficient (20-100°C) | 10.3 × 10⁻⁶ /K |
| Magnetic permeability | Ferromagnetic |
Available Dimensions
SHUNFU METAL supplies AISI 420, 1.4021 martensitic stainless steel in the following dimensions:
- Round Bars: Diameter range from 5 mm to 380 mm (0.197″ to 15″)
- Flat Bars: Thickness from 2 mm to 100 mm (0.079″ to 4″), width according to customer requirements
- Sheets and Plates: Thickness from 0.5 mm to 50 mm (0.02″ to 2″)
- Wire: Diameter from 0.1 mm to 12 mm (0.004″ to 0.472″)
- Forgings: According to customer specifications
- Pipes and Tubes: Outside diameter from 6 mm to 300 mm (0.236″ to 12″) with various wall thicknesses
Materials can be supplied in annealed, pre-hardened, or quenched and tempered condition. Custom dimensions and specifications are available upon request to meet specific project requirements.
Heat Treatment
AISI 420, 1.4021 achieves its optimal properties through a carefully controlled heat treatment process:
- Annealing: 800-850°C (1472-1562°F) followed by slow cooling
- Hardening (Austenitizing): 950-1050°C (1742-1922°F) followed by oil or air quenching
- Tempering: 150-750°C (302-1382°F) depending on desired hardness and toughness requirements
- Stress Relieving: 200-300°C (392-572°F) for 1-2 hours when required
AISI 420, 1.4021 can achieve hardness values up to 50-52 HRC when properly heat treated, with tempering temperature being the primary variable for adjusting final hardness and mechanical properties.
Tempering Chart
| Tempering Temperature | Approximate Hardness (HRC) | Typical Application |
|---|---|---|
| 150-200°C (302-392°F) | 48-52 | Cutting tools, surgical instruments |
| 300-400°C (572-752°F) | 42-48 | Knife blades, shear blades |
| 500-600°C (932-1112°F) | 30-40 | Valves, pump components |
| 650-750°C (1202-1382°F) | 22-28 | Maximum toughness applications |
Corrosion Resistance
AISI 420, 1.4021 martensitic stainless steel offers moderate corrosion resistance properties:
- General Corrosion: Good resistance to mild atmospheric conditions, fresh water, and weak organic and inorganic chemicals.
- Oxidation Resistance: Good resistance to scaling at temperatures up to approximately 650°C (1202°F).
- Pitting and Crevice Corrosion: Limited resistance to localized corrosion in chloride-containing environments.
- Stress Corrosion Cracking: Susceptible to SCC in chloride environments, particularly at elevated temperatures.
- Intergranular Corrosion: Can be susceptible after improper heat treatment; proper tempering minimizes this risk.
For optimal corrosion resistance, AISI 420, 1.4021 should be used in the hardened and tempered condition with a polished or passivated surface finish. It is important to note that higher hardness conditions (lower tempering temperatures) generally exhibit reduced corrosion resistance compared to lower hardness conditions (higher tempering temperatures).
Fabrication Characteristics
AISI 420, 1.4021 offers the following fabrication characteristics:
- Machinability: Good in the annealed condition (approximately 50-60% of free-cutting steel). Pre-machining in the annealed condition followed by final heat treatment is often recommended for precision components.
- Weldability: Limited due to high carbon content; preheating to 200-300°C (392-572°F) and post-weld heat treatment are typically required to prevent cracking.
- Formability: Good in the annealed condition; limited in the hardened condition.
- Grindability: Excellent in the hardened and tempered condition.
- Polishability: Excellent; can achieve mirror-like finishes.
Why Choose SHUNFU METAL for AISI 420, 1.4021
When sourcing AISI 420, 1.4021 martensitic stainless steel for your critical applications, SHUNFU METAL delivers superior quality and service. Our inventory of AISI 420, 1.4021 meets the most stringent industry standards and undergoes comprehensive quality control to ensure consistent performance across all heat treatment conditions. We provide complete material traceability and certification, including:
- Material test reports (MTR) documenting chemical composition
- Mechanical property certification
- Heat treatment documentation
- Dimensional tolerance verification
- Surface quality inspection reports
- Ultrasonic testing certification when required
Our technical experts can assist you in selecting the optimal heat treatment condition of AISI 420, 1.4021 for your specific application requirements, ensuring the ideal balance of hardness, strength, and toughness. With competitive pricing, reliable global shipping, and responsive customer service, we aim to be your trusted partner for specialty steel solutions.
Contact us today with your AISI 420, 1.4021 requirements. Our team is ready to provide detailed quotations and technical support to help you select the ideal material specification for your cutting tools, valve components, surgical instruments, or other demanding applications that require both strength and moderate corrosion resistance.
We are committed to integrate steel resources in china and serve the global steel market. Our company has more than 15 years of experience in steel researching, production, managing and sales. And our team mostly are based on and worked in national famous steel enterprise before. In the aspect of resources and information, we have established cooperative relationship with nearly hundred enterprises, either state-owned or private owned in China.
What’s more, we have built long, deep and close business relationship with dozens of steel company, Sharing and holding equities with several steel enterprises. Because of the close cooperation with steel companies and our pioneering spirit, which can ensure us stay at the top competition, and ensure our customers get what they really want. We provide preffesional one-stop service to the Contractors of follows project:
- Oil and Gas Pipeline Construction
- Onshore and Offshore
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- Heating & Air Conditioning
Our ability to purchase materials directly from leading mills at the best possible price will give you the competitive edge. This coupled with a skilled workforce dedicated to embracing the demands of the markets we serve. Just give us a call +86-731-89903933.
