316 is a molybdenum-bearing austenitic stainless with better corrosion resistance than 304 — and slightly worse machinability. It is gummier and work-hardens just as fast, so run a touch slower and never let the tool dwell.
Key properties
| Property | Typical value |
|---|---|
| Density | 0.289 lb/in³ (8.00 g/cm³) |
| Hardness | ~79 HRB |
| Tensile strength | ~84,000 psi (580 MPa) |
| Machinability | Fair (work-hardens) |
| Composition | Fe with Cr, Ni, Mo |
Cutting speeds
| Operation | HSS (SFM) | Carbide (SFM) |
|---|---|---|
| Milling | 35 – 55 | 130 – 280 |
| Turning | 45 – 65 | 180 – 330 |
| Drilling | 25 – 45 | 90 – 180 |
Convert to RPM: RPM = (SFM × 3.82) / cutter diameter. Use the Feeds & Speeds calculators.
Tooling and tips
- Sharp TiAlN or AlTiN carbide, 4–5 flutes, variable helix, very rigid setup.
- Heavy flood coolant; commit to a real chip and never dwell.
- Treat it like 304 but a step slower and gummier.
See Cutting Speeds for Stainless Steel and the full Feeds and Speeds Chart.