MATERIALS · STAINLESS STEEL
AISI 316 / 316L / 1.4401 / 1.4404. SS316 adds molybdenum (2.0–2.5% in EN 10088, 2.0–3.0% in ASTM) to an austenitic chromium-nickel base, which gives better resistance to pitting and crevice corrosion in chloride environments than 304. 316L is the low-carbon version (0.030% C max) preferred for welded parts. It is often called marine grade, although it is not resistant to warm sea water.
DENSITY
8 g/cm³HARDNESS
215 HB maxTENSILE STRENGTH
500–700 MPaMACHINABILITY
Fair (45%)TURNING, CARBIDE
80–150 m/minCALCULATOR
Enter your part size and your own rates. Density and a starting cutting speed are filled in for this material.
EQUIVALENT GRADES
Nearest equivalents across standards. Check the exact standard on critical parts.
| Standard | Grade |
|---|---|
| AISI/SAE | 316 / 316L |
| UNS | S31600 / S31603 |
| EN / W.Nr | X5CrNiMo17-12-2 / 1.4401; X2CrNiMo17-12-2 / 1.4404 |
| IS | X04Cr17Ni12Mo2 / X02Cr17Ni12Mo2 (IS 6603) |
| JIS | SUS316 / SUS316L |
| BS | 316S31 / 316S11 |
Also known as: 316, 316L, 1.4401, 1.4404, X5CrNiMo17-12-2, X2CrNiMo17-12-2, SUS316, marine grade stainless
CHEMICAL COMPOSITION
| Element | Weight % |
|---|---|
| C | ≤0.07 for 316 (ASTM ≤0.08); ≤0.030 for 316L |
| Si | ≤1.00 |
| Mn | ≤2.00 |
| P | ≤0.045 |
| S | ≤0.030 |
| Cr | 16.5–18.5 (EN 10088-3); 16.0–18.0 (ASTM) |
| Ni | 10.0–13.0 (EN 10088-3); 10.0–14.0 (ASTM) |
| Mo | 2.00–2.50 (EN 10088-3); 2.00–3.00 (ASTM) |
| N | ≤0.10 |
MECHANICAL PROPERTIES
| Condition | Solution annealed bar, EN 10088-3 (up to 160 mm), 1.4401 and 1.4404; ASTM A276 minimums in brackets |
| Tensile strength (MPa) | 500–700 (ASTM: 316 515 min, 316L 485 min) |
| Yield strength (MPa) | 200 min (ASTM: 316 205 min, 316L 170 min) |
| Elongation (%) | 40 min |
| Hardness | 215 HB max |
| Density (g/cm³) | 8 |
MACHINING
| Turning, carbide (m/min) | 80–150 |
| Turning, HSS (m/min) | 18–30 |
| Machinability | Fair, 45% (AISI B1112 = 100% (published figures 42–45%; usually run about 10% slower than 304)) |
316 machines much like 304 but is a little harder on tools, so start roughly 10% slower. Keep the same discipline: sharp positive-rake edges, a steady feed, no dwelling, and a depth of cut that gets under the work-hardened layer. Interrupted cuts or too light a feed leave a hardened surface that is difficult to cut on the next pass. Use chip-breaker geometry for the long chips and plenty of coolant. Clean off all cutting fluid after machining so the surface can re-passivate, especially on parts going into chloride service.
APPLICATIONS
INDUSTRIES THAT USE IT
PROCESSING
| Heat treatment | Cannot be hardened by heat treatment. Solution anneal at 1010–1120 °C and cool rapidly; use 316L where parts must spend time at 425–860 °C, as it resists carbide precipitation. |
| Welding | Excellent by all standard fusion methods; use 316 or 316L filler, and choose 316L for heavy welded sections that cannot be annealed afterwards. |
| Supplied as | Round bar, Bright bar, Sheet, Strip, Plate, Pipe, Tube, Angle |
QUESTIONS
316 is usually called marine grade because molybdenum improves its resistance to chlorides, but it is not resistant to warm sea water. In marine air it can show brown surface staining, mainly in crevices and on rough finishes, so smooth finishes and regular cleaning help.
316L has carbon limited to 0.030% max, so it resists carbide precipitation during welding and heavy welded sections need no post-weld anneal. 316 has slightly higher specified strength in ASTM standards. Plate and pipe are often stocked dual-certified to both grades.
In the annealed condition 316 responds only negligibly to a magnet. Cold working can raise its magnetic response slightly because some of the austenite transforms to martensite.
RELATED MATERIALS
STAINLESS STEEL
AISI 303 / 1.4305 · 8 g/cm³
STAINLESS STEEL
AISI 304 / 1.4301 · 8 g/cm³
STAINLESS STEEL
AISI 410 / 1.4006 · 7.75 g/cm³
STAINLESS STEEL
AISI 630 (17-4 PH) / 1.4542 · 7.75 g/cm³
Data reviewed 2026-10-02 against:
Typical values for reference. Always check the mill certificate and the standard your customer specifies.
Book a free 30-minute visit. We'll run one of your real jobs through Kojo on the spot. Outside India? We'll do it on a video call.
Book a factory visit