440B
Data verified440B is the middle member of the 440 series, with carbon between 440A and 440C, balancing edge hardness against toughness and corrosion resistance in cutlery and bearing applications.
Chemical composition
| Element | Content (%) |
|---|---|
| C | 0.75–0.95 |
| Si | ≤1.00 |
| Mn | ≤1.00 |
| P | ≤0.040 |
| S | ≤0.030 |
| Cr | 16.00–18.00 |
| Mo | ≤0.75 |
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) | 56–59 HRC |
| Tensile strength | 740–1960 MPa (condition dependent) |
| Density | 7.70 g/cm³ |
| Magnetic | Yes |
Heat treatment
Anneal 845–900 °C slow cool; harden 1010–1065 °C oil/air; temper 150–370 °C.
Equivalent grades
| Standard | Designation |
|---|---|
| aisi | 440B |
| jis | SUS440B |
Compare side by side: 440B vs 440A · 440B vs 440C
Equivalents overlap in chemistry and use but are not always identical — see our equivalents guide before substituting in certified designs.
Applications & Processing
Applications: Premium cutlery, bearings, valve components, surgical tools.
Processing: As 440A but with more carbide: slower to grind and finish; best corrosion performance in the hardened and polished state.
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Ask for a quotationVisit NasteelSource: ASTM A276 published ranges · Last updated 2026-11-03. Data is indicative — verify critical values against the governing standard and mill certificate before use.