W1
Data under reviewW1 is the classic water-hardening carbon tool steel, ordered by carbon class from about 0.70% to 1.30% C. It forms a very hard thin case over a tough soft core — the oldest tool steel still in daily use.
Chemical composition
| Element | Content (%) |
|---|---|
| C | 0.70–1.30 (by carbon class) |
| Si | 0.10–0.40 |
| Mn | 0.10–0.40 |
Weight percent, per the governing standard ranges. Actual values per heat are on the mill certificate.
Properties
| Delivery condition | Annealed |
| Hardness (hardened) | 58–65 HRC (surface, shallow case) |
| Density | 7.85 g/cm³ |
| Hardenability | Shallow (water quench) |
Heat treatment
Harden 760–830 °C in water or brine (temperature follows carbon class); temper 150–300 °C immediately.
Equivalent grades
| Standard | Designation |
|---|---|
| din | 1.1545 (C105W1, by carbon class) |
| aisi | W1 |
| jis | SK3 family (by carbon class) |
| gb | T10 (near, by carbon class) |
Compare side by side: W1 vs O1
Equivalents overlap in chemistry and use but are not always identical — see our equivalents guide before substituting in certified designs.
Applications & Processing
Applications: Hand tools, files rasps and scrapers, razors, woodworking edges, small dies, punches for light duty.
Processing: Cheapest tool steel to buy and to harden, but the violent water quench cracks intricate shapes and the shallow case limits size. For production dies, O1/A2 are safer.
FAQ
- Why is W1 sold by carbon class?
- One grade name covers many carbon levels; the class (e.g. 1.00% C) is picked for the balance of case hardness and core toughness the tool needs.
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Ask for a quotationVisit NasteelSource: ASTM A686 published ranges · Last updated 2026-11-03. Data is indicative — verify critical values against the governing standard and mill certificate before use.