440C / X105CrMo17
1.4125Highest-hardness standard martensitic stainless steel. Achieves 57-60 HRC — the hardest commonly available stainless grade. Excellent wear resistance from chromium carbides. Used for bearings, races, valve components, surgical instruments, high-end cutlery, and precision molds.
International equivalents
| Flag | Standard | Country | Grade | Number | Match |
|---|---|---|---|---|---|
| 🇺🇸 | AISI | USA | AISI 440C | S44004 | REF |
| 🇪🇺 | EN | Europe | X105CrMo17 | 1.4125 | 100% |
| 🇯🇵 | JIS | Japan | SUS440C | — | 97% |
| 🇨🇳 | GB | China | 9Cr18Mo | — | 93% |
Sources: ASTM A276, EN 10088-3, JIS G4303, GB/T 1220
Mechanical properties
Compatibility verdict
440C / X105CrMo17 and SUS440C: 97% composition match
Related materials
304 Stainless Steel
1.4301The most widely used austenitic stainless steel. Excellent corrosion resistance, good formability and weldability. Standard choice for food processing, chemical, and architectural applications.
316L
1.4404Low-carbon austenitic stainless steel with molybdenum addition. Superior corrosion resistance to 304, especially against chlorides and pitting. Standard choice for chemical processing, marine, medical implants, and pharmaceutical equipment.
430 Stainless Steel
1.4016Ferritic chromium stainless steel with good corrosion resistance and formability. Lower cost than austenitic grades. Used for automotive trim, kitchen sinks, architectural panels, and appliance components.
Export this comparison as PDF
Professional datasheet with equivalents, composition, and properties. Ready for your QM documentation.
Download PDF — €4.90Included with PRO subscription