420
Data verified420 is a hardenable 13% chromium martensitic stainless used for cutlery, surgical instruments and wear parts. Note: DIN 1.2083 is the high-carbon (0.36–0.42% C) mold-steel variant of the 420 family, melted and specified for plastic mold cavities rather than general engineering use.
Chemical composition
| Element | Content (%) |
|---|---|
| C | ≥0.15 |
| Si | ≤1.00 |
| Mn | ≤1.00 |
| P | ≤0.040 |
| S | ≤0.030 |
| Cr | 12.00–14.00 |
Weight percent, per the governing standard ranges. Actual values per heat are on the mill certificate.
Properties
| Delivery condition | Annealed (hardened for use) |
| Hardness (hardened) | 48–55 HRC |
| Tensile strength | 655–1700 MPa (condition dependent) |
| Density | 7.70 g/cm³ |
| Magnetic | Yes |
Heat treatment
Anneal 840–900 °C slow cool; harden 980–1035 °C oil/air; temper 150–370 °C for cutlery hardness, higher for toughness.
Equivalent grades
| Standard | Designation |
|---|---|
| din | 1.4021 |
| aisi | 420 |
| jis | SUS420J1 |
| gb | 20Cr13 |
Equivalents overlap in chemistry and use but are not always identical — see our equivalents guide before substituting in certified designs.
Applications & Processing
Applications: Knife blades, surgical and dental instruments, needle valves, shear blades, hand tools.
Processing: Best corrosion resistance is achieved in the hardened and polished condition; weldability is poor and rarely attempted; machines acceptably when annealed.
FAQ
- 420 vs 440C for knives?
- 440C carries about 1% carbon and 17% chromium, reaching 58–60 HRC with better edge retention and corrosion resistance; 420 is tougher, cheaper and easier to sharpen, common in budget and diving knives.
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Ask for a quotationVisit NasteelSource: ASTM A276 / EN 10088 published ranges · Last updated 2026-11-03. Data is indicative — verify critical values against the governing standard and mill certificate before use.