403
Data verified403 is a 12% chromium martensitic stainless developed for steam turbine blades, where controlled cleanliness and temper response matter more than maximum hardness. It is the quality-controlled sibling of 410.
Chemical composition
| Element | Content (%) |
|---|---|
| C | ≤0.15 |
| Si | ≤0.50 |
| Mn | ≤1.00 |
| P | ≤0.040 |
| S | ≤0.030 |
| Cr | 11.50–13.00 |
Weight percent, per the governing standard ranges. Actual values per heat are on the mill certificate.
Properties
| Delivery condition | Annealed or hardened & tempered |
| Hardness (hardened) | 35–45 HRC typical |
| Tensile strength | 485–1400 MPa (condition dependent) |
| Density | 7.70 g/cm³ |
| Magnetic | Yes |
Heat treatment
Anneal 845–900 °C furnace cool; harden 955–1010 °C oil/air; temper 205–650 °C to the required strength level.
Equivalent grades
| Standard | Designation |
|---|---|
| din | 1.4000 |
| aisi | 403 |
| jis | SUS403 |
| gb | 12Cr13 |
Compare side by side: 403 vs 410
Equivalents overlap in chemistry and use but are not always identical — see our equivalents guide before substituting in certified designs.
Applications & Processing
Applications: Steam turbine blades, compressor blades, valve parts, high-strength fasteners.
Processing: Hardenable by quench and temper; weldable with preheat and post-weld temper; machinability moderate in the annealed state.
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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.