S55C
Data verifiedS55C is the higher-carbon member of the JIS G4051 family (AISI 1055 / EN C55 class), used where a carbon steel must take real surface hardness — rails, shafts, gears of moderate duty and wear parts in Asian machinery.
Chemical composition
| Element | Content (%) |
|---|---|
| C | 0.52–0.58 |
| Si | 0.15–0.35 |
| Mn | 0.60–0.90 |
| P | ≤0.030 |
| S | ≤0.035 |
Weight percent, per the governing standard ranges. Actual values per heat are on the mill certificate.
Properties
| Tensile strength | ≥650 MPa (normalized, JIS reference) |
| Density | 7.85 g/cm³ |
Heat treatment
Normalize 830–860 °C; quench 830–850 °C oil; temper 500–600 °C. Induction hardening is the standard surface treatment.
Equivalent grades
| Standard | Designation |
|---|---|
| din | C55 (1.0535) |
| aisi | 1055 |
| jis | S55C (JIS G4051) |
| gb | 55 |
Compare side by side: S55C vs 1055 · S55C vs S50C
Equivalents overlap in chemistry and use but are not always identical — see our equivalents guide before substituting in certified designs.
Applications & Processing
Applications: Shafts, guide rails, gears and sprockets, wear plates of moderate duty, agricultural tools.
Processing: Induction/flame hardening to 55+ HRC surface is routine; welding needs preheat and is avoided where possible at this carbon level.
FAQ
- S55C vs S50C?
- S55C carries more carbon (0.52–0.58% vs 0.47–0.53%), giving higher achievable surface hardness and wear life, with a little less toughness and weldability. Both are stocked across Asia as bar and plate.
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Ask for a quotationVisit NasteelSource: JIS G4051 published ranges · Last updated 2026-11-03. Data is indicative — verify critical values against the governing standard and mill certificate before use.