4620
Data verified4620 is a Ni-Mo carburizing steel without chromium: the nickel-molybdenum pair gives a tough, ductile core and a case that resists spalling. It is used for gears and cams where core toughness matters more than case depth.
Chemical composition
| Element | Content (%) |
|---|---|
| C | 0.18–0.23 |
| Si | 0.15–0.35 |
| Mn | 0.45–0.65 |
| P | ≤0.035 |
| S | ≤0.040 |
| Ni | 1.65–2.00 |
| Mo | 0.20–0.30 |
Weight percent, per the governing standard ranges. Actual values per heat are on the mill certificate.
Properties
| Case hardness (carburized) | 58–62 HRC |
| Core tensile strength | 700–950 MPa (typ.) |
| Density | 7.85 g/cm³ |
Heat treatment
Carburize 900–930 °C; quench 790–820 °C oil; temper 150–200 °C.
Equivalent grades
| Standard | Designation |
|---|---|
| aisi | 4620 |
| jis | SNCM220 family (near) |
Compare side by side: 4620 vs 4320
Equivalents overlap in chemistry and use but are not always identical — see our equivalents guide before substituting in certified designs.
Applications & Processing
Applications: Gears, camshafts, piston pins, heavy-duty chain parts.
Processing: Good machinability; slightly lower hardenability than 4320 — watch section size.
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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.