H12
Data verifiedH12 is an H13-family hot work steel with about 1.5% tungsten added and slightly less vanadium. The tungsten improves resistance to softening while toughness stays high, suiting severe thermal shock duty.
Chemical composition
| Element | Content (%) |
|---|---|
| C | 0.30–0.40 |
| Si | 0.80–1.25 |
| Mn | 0.20–0.60 |
| Cr | 4.75–5.50 |
| Mo | 1.25–1.75 |
| W | 1.00–1.75 |
| V | 0.20–0.50 |
Weight percent, per the governing standard ranges. Actual values per heat are on the mill certificate.
Properties
| Delivery condition | Annealed |
| Working hardness | 40–52 HRC |
| Density | 7.80 g/cm³ |
| Toughness | Better than H13 at equal hardness |
Heat treatment
Harden 1000–1050 °C air/oil; double temper 550–620 °C.
Equivalent grades
| Standard | Designation |
|---|---|
| din | 1.2606 |
| aisi | H12 |
| jis | SKD62 |
| gb | 4Cr5MoWSiV (near) |
Compare side by side: H12 vs H13 · H12 vs H10 · H12 vs SKD61
Equivalents overlap in chemistry and use but are not always identical — see our equivalents guide before substituting in certified designs.
Applications & Processing
Applications: Die casting dies, extrusion dies, hot grips and headers, forging dies with water cooling.
Processing: Similar practice to H13; often picked where H13 cracks early under aggressive die cooling.
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Ask for a quotationVisit NasteelSource: ASTM A681 / EN ISO 4957 published ranges · Last updated 2026-11-03. Data is indicative — verify critical values against the governing standard and mill certificate before use.