FUSHUN METAL / Martensitic Stainless Steel
420 Stainless Steel
High-carbon martensitic grade with 12–14% chromium. Achieves up to 500 HB hardness—the highest of any standard chromium stainless grade. Excellent machinability when annealed; optimal corrosion resistance when hardened and polished.
Product Overview
420 Stainless Steel is a premium martensitic stainless steel characterized by its 12% to 14% chromium content, which provides excellent corrosion resistance when hardened and polished. Compared to other standard martensitic grades, 420 stainless steel features a higher carbon content, enabling it to achieve remarkable hardness levels up to 500 HB—the highest among standard chromium grades. In its annealed condition, this steel exhibits good ductility and excellent machinability, making it easy to form before the final hardening process.
Because of its martensitic structure, 420 stainless steel is magnetic in all conditions. Its optimal corrosion resistance is achieved when the metal is hardened and the surface is finely ground or polished, providing excellent protection against fresh water, alkalis, mild acids, and food substances.
At FUSHUN METAL, we leverage decades of metallurgical expertise to supply 420 stainless steel with exceptional purity and structural uniformity, ensuring reliable performance in high-wear and moderately corrosive environments. Whether you require standard dimensions or custom-forged profiles, our robust production capabilities guarantee materials that meet the most stringent engineering demands.
International Equivalent Grades
| US / International | Europe (EN) | Japan (JIS) | China (GB/T) |
|---|---|---|---|
| AISI 420 / UNS S42000 | 1.4021 (X20Cr13) / 1.4028 (X30Cr13) | SUS420J1 / SUS420J2 | 20Cr13 / 30Cr13 |
Applications
Thanks to its combination of high hardness and good corrosion resistance, 420 stainless steel is widely used across demanding industries. Its ability to be hardened to a razor-sharp edge while resisting mild corrosive media makes it the material of choice for precision instruments, cutting tools, and wear-resistant mechanical components. Typical downstream products and applications include:
- Surgical and dental instruments
- High-quality cutlery, carving knives, and table knives
- Shear blades and industrial cutting hand tools
- Needle valves and pump shafts
- Plastic injection molds requiring moderate corrosion resistance
- Gear pinions, cams, and pivot pins
- Measuring tools and precision straight edges
Specifications & Standards
FUSHUN METAL supplies 420 stainless steel in strict accordance with major international standards. The grade is officially recognized and specified in the following frameworks:
- ASTM A276 / A276M
- Standard Specification for Stainless Steel Bars and Shapes
- ASTM A314
- Standard Specification for Stainless Steel Billets and Bars for Forging
- ASTM A176
- Standard Specification for Stainless and Heat-Resisting Chromium Steel Plate, Sheet, and Strip
- EN 10088-3
- Stainless steels — Technical delivery conditions for semi-finished products, bars, rods, wire, and sections
- JIS G4303
- Stainless steel bars
- GB/T 1220
- Stainless steel bars
Available Sizes & Delivery
FUSHUN METAL is equipped with state-of-the-art manufacturing facilities including a powerful 6000-ton forging press and an advanced GFM radial forging machine, enabling us to offer an exceptionally wide range of product forms and sizes to match your exact project requirements.
Available Shapes & Size Range
| Product Form | Dimension Range |
|---|---|
| Rolled Round Bars | Dia 8mm – 130mm |
| Forged Round Bars | Dia 130mm – 800mm |
| Rolled Flat Bars | Thickness 10mm – 80mm × Width 20mm – 150mm |
| Forged Flat Bars / Blocks | Thickness 80mm – 500mm × Width 100mm – 1000mm |
| Plates & Sheets | Thickness 1mm – 150mm |
| Steel Wire | Dia 1mm – 8mm |
Delivery & Minimum Order Quantity (MOQ)
Ready Stock
Common sizes available with no MOQ (1 piece minimum). Rapid delivery time of approximately 7 days.
Custom Forgings / Rolled Products
For non-standard dimensions, MOQ is typically 3 tons with a lead time of around 30 days.
Small Induction Furnace Melts
Flexible induction furnaces accommodate custom smelting runs from as little as 3 to 5 tons.
Large-Scale Industrial Orders
Supported by 30–60 ton Electric Arc Furnaces for fast, stable delivery of bulk industrial projects.
Chemical Composition
The chemical composition of 420 stainless steel varies slightly depending on the specific standard and regional designation. The table below provides a cross-standard comparison of elemental limits. Highlighted cells mark the principal variations in Carbon and Manganese content between standards.
| Standard / Grade | C (%) | Si (%) | Mn (%) | P (%) | S (%) | Cr (%) | Ni (%) | Mo (%) |
|---|---|---|---|---|---|---|---|---|
| AISI 420 | ≥ 0.15 | ≤ 1.00 | ≤ 1.00 | ≤ 0.040 | ≤ 0.030 | 12.0–14.0 | ≤ 0.75 | ≤ 0.50 |
| EN 1.4021 | 0.16–0.25 | ≤ 1.00 | ≤ 1.50 | ≤ 0.040 | ≤ 0.030 | 12.0–14.0 | — | — |
| JIS SUS420J1 | 0.16–0.25 | ≤ 1.00 | ≤ 1.00 | ≤ 0.040 | ≤ 0.030 | 12.0–14.0 | ≤ 0.60 | — |
| JIS SUS420J2 | 0.26–0.40 | ≤ 1.00 | ≤ 1.00 | ≤ 0.040 | ≤ 0.030 | 12.0–14.0 | ≤ 0.60 | — |
Melting & Processing Routes
At FUSHUN METAL, we understand that material purity directly impacts the final performance of your components. We offer flexible, multi-tier melting routes tailored to your specific application requirements. Our standard production for 420 stainless steel utilizes an Electric Arc Furnace (EAF) combined with Argon Oxygen Decarburization (AOD) for precise carbon and chromium control, followed by Ladle Furnace (LF) and Vacuum Degassing (VD). Contact our engineering team to select the most cost-effective and technically suitable route for your project.
Precise carbon and chromium control via Argon Oxygen Decarburization, followed by Ladle Furnace refining and Vacuum Degassing. Suitable for general engineering and tooling applications.
Electro-Slag Remelting delivers superior inclusion cleanliness and enhanced fatigue life. Specified for demanding mold steel, high-performance tooling, and components requiring improved impact toughness.
Vacuum Induction Melting followed by Vacuum Arc Remelting guarantees the highest level of micro-cleanliness and chemical homogeneity. Specified for aerospace and medical-grade components.
Mechanical Properties
The mechanical properties of 420 stainless steel are highly dependent on the chosen heat treatment condition. The table below lists typical room-temperature properties in the annealed condition and at various tempering temperatures following hardening. Note that tempering within the 427°C–538°C range (highlighted rows) is generally avoided due to a significant drop in impact toughness and corrosion resistance.
| Condition / Tempering Temp (°C) | Tensile Strength (MPa) | Yield Strength 0.2% (MPa) | Elongation (% in 50mm) | Hardness (HB) | Impact Charpy V (J) |
|---|---|---|---|---|---|
| Annealed | 655 | 345 | 25 | ≤ 241 | — |
| Hardened + Tempered at 204°C | 1600 | 1360 | 12 | 444 | 20 |
| Hardened + Tempered at 316°C | 1580 | 1365 | 14 | 444 | 19 |
| Hardened + Tempered at 427°C | 1620 | 1420 | 10 | 461 | — |
| Hardened + Tempered at 538°C | 1305 | 1095 | 15 | 375 | — |
| Hardened + Tempered at 593°C | 1035 | 810 | 18 | 302 | 22 |
| Hardened + Tempered at 650°C | 895 | 680 | 20 | 262 | 42 |
Heat Treatment
Proper heat treatment is critical to unlocking the full performance potential of 420 stainless steel. FUSHUN METAL delivers material in the annealed condition as standard for optimal machinability. Pre-hardened material and customer-specified heat treatment conditions are available upon request.
| Process | Temperature Range | Soaking Time | Cooling Method |
|---|---|---|---|
| Annealing | 816°C – 899°C (1500°F – 1650°F) | 2 to 4 hours (depending on section thickness) | Cool slowly in furnace to 600°C, then air cool |
| Stress Relieving | 149°C – 427°C (300°F – 800°F) | 1 to 3 hours | Air cool, or quench in oil / water |
| Hardening (Austenitizing) | 982°C – 1066°C (1800°F – 1950°F) | 30 minutes per inch of thickness | Air cool or quench in warm oil |
| Tempering | 150°C – 650°C (Avoid 427°C–538°C) | 1 to 2 hours | Air cool |
Surface Finish & Machining
FUSHUN METAL offers a comprehensive range of surface conditions to minimize your downstream processing time and total machining cost. In its annealed state, 420 stainless steel machines readily using conventional tooling; however, machinability decreases significantly once hardness exceeds 30 HRC, at which point precision grinding becomes the preferred finishing method.
Available Surface Conditions
- Raw forged or rolled black surface (as-processed, scale intact)
- Rough turning & peeling to remove scale and achieve uniform OD
- Milling on flat bars and blocks (single or multi-face)
- CNC machining on all six faces to exact customer specifications
- Precision centerless grinding for round bars: dimensional tolerance h9 / h11; surface roughness Ra 0.8–1.6 µm
Machinability Reference
- Excellent machinability in fully annealed condition (max 241 HB)
- Conventional HSS or carbide tooling suitable for annealed state
- Machinability degrades markedly above 30 HRC
- Grinding is the preferred method for hardened components
- Cutting fluid (coolant) strongly recommended throughout all machining operations to manage heat generation and extend tool life
Quality Assurance & Inspection
Quality is the cornerstone of FUSHUN METAL’s operations. Our rigorous QA/QC system ensures that every piece of 420 stainless steel meets your exact specifications before it leaves our facility. All production is governed by our ISO 9001 and AS9100 certified quality management systems.
Ultrasonic Testing (UT)
100% volumetric UT inspection for internal flaws, executed per SEP 1921 Class C/c, D/d, or customized aerospace acceptance criteria.
Comprehensive In-House Testing
OES chemical composition analysis, full mechanical property testing (tensile, yield, impact, hardness), and precise dimensional verification.
Metallographic Examination
Microstructure analysis to confirm uniform grain size and the absence of detrimental non-metallic inclusions or segregation.
Mill Test Certificates
Full material traceability via EN 10204 3.1 MTC as standard. Third-party endorsed EN 10204 3.2 certification available upon request.
Third-Party Inspection
We regularly coordinate with internationally recognized agencies including SGS, TÜV, and Bureau Veritas to support customer hold points.
Certified Management Systems
ISO 9001 and AS9100 quality management systems govern all production, inspection, and documentation processes across our facility.
Packing & Shipping
Industrial materials must arrive at your facility in pristine condition. FUSHUN METAL applies a differentiated packaging strategy based on surface condition, engineered to withstand long-distance oceanic transit and variable climate conditions.
Standard Industrial Bundling
- Heavy-duty steel wire bundling with secure strapping on each bundle
- Prevents shifting, abrasion, and end-damage inside shipping containers
- Suitable for as-rolled bars, as-forged blocks, and rough-turned products
Multi-Layer Protective Packaging
- Full coating with premium anti-rust oil on all exposed surfaces
- Individually wrapped in waterproof VCI (Volatile Corrosion Inhibitor) paper
- Secured inside reinforced, fumigated wooden crates
- Preserves surface roughness Ra and dimensional accuracy throughout transit
- Guarantees completely rust-free delivery after extended oceanic shipping
Get in Touch with Our Technical Team
Request a Quote for 420 Stainless Steel
Provide your grade, product form, dimensions, quantity, and certification requirements. Our technically trained sales engineers will respond within 24 hours with a competitive quotation and a full technical datasheet.
Or email us directly at info@fushunspecialsteel.com
Frequently Asked Questions
Below are answers to the most common technical and commercial questions about 420 stainless steel. For project-specific requirements not covered here, please contact our engineering team directly.
