L6
Data verifiedL6 is a nickel-chromium oil-hardening steel prized for toughness in large tools. The nickel content deepens hardening and keeps big sections from going brittle.
Chemical composition
| Element | Content (%) |
|---|---|
| C | 0.65–0.75 |
| Si | 0.10–0.50 |
| Mn | 0.25–0.80 |
| Cr | 0.60–1.00 |
| Ni | 1.25–2.00 |
| Mo | ≤0.50 |
Weight percent, per the governing standard ranges. Actual values per heat are on the mill certificate.
Properties
| Delivery condition | Annealed |
| Hardness (hardened) | 50–58 HRC |
| Density | 7.85 g/cm³ |
| Toughness | Very high (nickel-bearing) |
Heat treatment
Harden 790–870 °C oil; temper 175–540 °C by application.
Equivalent grades
| Standard | Designation |
|---|---|
| din | 1.2714 (family) |
| aisi | L6 |
| jis | SKT4 (near) |
| gb | 5CrNiMo (near) |
Compare side by side: L6 vs 5CrNiMo · L6 vs L2
Equivalents overlap in chemistry and use but are not always identical — see our equivalents guide before substituting in certified designs.
Applications & Processing
Applications: Large forming rolls, coining dies, blanking dies in heavy sections, clutches, snap rings, hot forging die blocks (family overlap with 5CrNiMo).
Processing: Machines well; oil quench with care in very large sections. Often supplied prehardened for die blocks.
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Ask for a quotationVisit NasteelSource: ASTM A681 published ranges · Last updated 2026-11-03. Data is indicative — verify critical values against the governing standard and mill certificate before use.