420HC Stainless Steel
420HC is a high-carbon version of the 420 family. It is chosen when you need higher hardness and better edge holding than standard 420, while keeping dependable corrosion resistance for daily-use environments. It is widely used for blades, cutting tools, and wear parts where performance and cost must stay balanced.
As a martensitic stainless steel, 420HC is magnetic and heat treatable. The final result depends on heat treatment control, surface finishing, and how the part is used in service.
Grade type
Martensitic, high carbon
Designed for hardness and wear resistance.
Hardness after heat treatment
Typically 54–58 HRC
Common target for blades and cutters.
Corrosion performance
Stable in mild service
Best with a polished, clean surface.
Core advantage
Heat treatable
A clear heat treatment plan is essential.
420HC is used for components that need a strong edge or wear surface, while still keeping practical corrosion resistance in normal working environments.
- Knife blades: outdoor, utility, kitchen, and general-purpose blades
- Medical and instrument parts: selected tools that require hardness and cleanability
- Cutting and wear parts: cutters, wear plates, guide parts, and small wear components
- Mechanical parts: shafts, pins, and precision components in mild corrosion exposure
- Mold inserts: inserts that need moderate corrosion resistance with a harder surface
“420HC” is widely used as a commercial name. Equivalent references help for cross-checking, but a purchase order should always state the target standard, product form, heat treatment condition, and test scope.
| System | Designation | Note |
|---|---|---|
| ASTM / AISI | 420HC (commercial name) | Common in blade and tool supply chains |
| UNS | S42000 | Widely used reference for ordering and MTC |
| EN | 1.4034 | Often used as a close European reference |
| DIN | X46Cr13 | Common format naming in documents |
| GOST | 40Х13 | Regional designation often seen in specs |
| JIS (reference) | SUS420J2 (commonly referenced) | Use chemistry on the MTC to confirm match |
- Higher hardness potential: supports better edge holding than standard 420.
- Balanced corrosion resistance: suitable for humidity, food contact, and mild chemicals.
- Machinability: typically best in the annealed condition, before heat treatment.
- Stable supply route: common in bars, plate, and cut-to-size components.
- Magnetic: magnetic in both annealed and hardened conditions.
Actual limits depend on the applied standard. The Mill Test Certificate is the final verification for your delivered heat.
| Basis | C | Cr | Mn | Si | P | S | Fe |
|---|---|---|---|---|---|---|---|
| Common 1.4034 / X46Cr13 reference | 0.43–0.50 | 12.5–14.5 | ≤ 1.0 | ≤ 1.0 | ≤ 0.04 | ≤ 0.015 (≤ 0.030 by agreement) | Balance |
Properties vary with section size, product form, and heat treatment. Use the governing specification for design and acceptance.
| Condition | Hardness | Tensile | Yield (0.2%) | Elongation |
|---|---|---|---|---|
| Annealed (reference) | ≤ 245 HB | Varies by thickness | Varies by thickness | Varies by thickness |
| Quenched & tempered (typical) | 54–58 HRC | ~850–1150 MPa | ~650–750 MPa | ~7–12% |
420HC performs well in everyday environments such as indoor air, humidity, and typical food-contact use when the surface is clean and polished. Like other martensitic grades, it performs best when properly heat treated and finished.
It is not recommended for long exposure to saltwater, heavy chlorides, or aggressive acids. If your service is high-chloride, select a grade designed for that environment.
420HC can be supplied in common stainless product forms. Availability depends on finish, tolerance, straightness, and inspection scope. Share your sizes and end use to align the best supply route.
| Form | Typical size range | Notes |
|---|---|---|
| Sheet (cold rolled) | 0.3–6.0 mm, width 1000–2000 mm | Common for cut-to-length and finishing |
| Plate (hot rolled) | 3–100 mm, width 1000–2000 mm | Used for machining stock and wear parts |
| Coil (cold rolled) | 0.3–6.0 mm, width 1000–2000 mm | Slitting and cut-to-length available |
| Coil (hot rolled) | 3–14 mm, width 1000–2000 mm | For heavier coil supply routes |
| Strip | 0.3–10 mm, width 7–600 mm | Often used for formed and stamped parts |
| Seamless pipe | OD ≤ 610 mm, WT 1–100 mm | Confirm NDT and straightness if required |
| Welded pipe | OD 6–3000 mm, WT 1–100 mm | Define weld type and surface requirements |
| Round bar | Diameter 1–200 mm, length 100–12000 mm | Common for machining and heat treatment |
| Flat bar / shapes | Flat width 20–800 mm, thickness 3–60 mm | Angles, channels, beams available upon request |
- Machining: usually best in annealed condition. Use sharp tooling and stable cutting fluids.
- Forming: possible for simple forming, but high-carbon martensitic grades are not designed for deep drawing.
- Welding: possible with controlled procedures. To reduce cracking risk, use preheat and consider post-weld tempering.
- Surface finishing: grinding and polishing help reduce stain marks in daily service.
- Quality control: define hardness range, straightness, and inspection scope in the order.
The right cycle depends on section size, hardness target, and distortion control requirements. Use trials for critical parts.
| Step | Typical range | Purpose |
|---|---|---|
| Anneal | 760–800°C, slow cool | Softens for machining and forming |
| Harden | 980–1050°C, oil or air quench | Builds hardness and strength |
| Temper | 150–400°C | Balances hardness with toughness |
These grades are commonly discussed for blades and wear components. 420HC is often selected as a balanced option: higher hardness than basic 420/J grades, but typically lower alloy level than 440 series.
| Grade | Hardness potential | Corrosion level | Typical positioning |
|---|---|---|---|
| 420J2 | Low–medium | Good | Cost-focused blades and formed parts |
| 420HC | Medium–high | Good | Quality blades and wear parts |
| 440A | High | Better | Premium blades, improved stain margin |
| 440C | Very high | Very good | High-end cutting and wear resistance |
Use these internal tools to confirm equivalents, check hardness, and prepare a clear RFQ before purchasing.
Is 420HC stainless steel magnetic?
Yes. 420HC is a martensitic stainless steel, so it is magnetic in both annealed and hardened conditions.
Is 420HC food safe?
It is widely used for food-contact blades. A polished surface and proper cleaning practice help reduce stain marks in use.
Does 420HC rust easily?
Not under normal daily conditions, but it is not designed for long saltwater exposure. For chloride-rich service, consider higher alloy grades.
What hardness is commonly used for knives?
Many users target about 55–57 HRC to balance edge holding and toughness. Final targets depend on blade geometry and use case.
What information helps you quote faster?
Grade and standard, product form, size range, surface finish, tolerance, quantity, required tests, packing request, and destination port. This supports a clear supply route and stable delivery planning.