8630
Data verified8630 is a Q&T Ni-Cr-Mo steel for cast and forged parts — wellheads, valves and aircraft components — where its castability and weldability made it an industry standard (often supplied as cast grade per ASTM A148/A487 practice).
Chemical composition
| Element | Content (%) |
|---|---|
| C | 0.28–0.33 |
| Si | 0.15–0.35 |
| Mn | 0.70–0.90 |
| P | ≤0.035 |
| S | ≤0.040 |
| Cr | 0.40–0.60 |
| Ni | 0.40–0.70 |
| Mo | 0.15–0.25 |
Weight percent, per the governing standard ranges. Actual values per heat are on the mill certificate.
Properties
| Hardness (Q&T) | 26–36 HRC typical |
| Tensile strength | 850–1050 MPa (Q&T, typ.) |
| Density | 7.85 g/cm³ |
Heat treatment
Normalize 870 °C; quench 855 °C oil; temper 540–660 °C.
Equivalent grades
| Standard | Designation |
|---|---|
| din | 30CrNiMo8 family is higher-alloy (near family) |
| aisi | 8630 |
Compare side by side: 8630 vs 8740 · 8630 vs 8640
Equivalents overlap in chemistry and use but are not always identical — see our equivalents guide before substituting in certified designs.
Applications & Processing
Applications: Wellhead and valve bodies, aircraft parts, forged fittings, pressure-containing parts.
Processing: Weldable with preheat 200–300 °C and qualified procedure; machines well annealed.
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Ask for a quotationVisit NasteelSource: SAE J404 published ranges · Last updated 2026-11-03. Data is indicative — verify critical values against the governing standard and mill certificate before use.