Stainless Steel Fasteners
Chromium-bearing steels with at least 10.5% Cr that form a passive oxide film. Austenitic grades (304, 316) are the most widely specified fastener stainless steels; martensitic 410 is hardenable.
Stainless Steel Fasteners
Chromium-bearing steels with at least 10.5% Cr that form a passive oxide film. Austenitic grades (304, 316) are the most widely specified fastener stainless steels; martensitic 410 is hardenable.
Common standards: ASTM F593, F594, A193 B8/B8M/B6, A194 Gr 8/8M, A276, ISO 3506-1/-2
Common Grades
| Grade | Description |
|---|---|
| 304 | A2 austenitic, general purpose |
| 304L | Low-carbon 304, better weld-zone corrosion resistance |
| 316 | A4 molybdenum-bearing, improved chloride resistance |
| 316L | Low-carbon 316 |
| 321 | Titanium-stabilised for elevated temperature |
| 347 | Niobium-stabilised for elevated temperature |
| 410 | Martensitic, hardenable, moderate corrosion resistance |
General industry information. Grades listed are not a statement of current stock or manufacture; availability is confirmed at enquiry.
Chemical Composition (% typical specification limits)
| Grade | C | Cr | Ni | Mo | Other |
|---|---|---|---|---|---|
| 304 | ≤0.08 | 18.0–20.0 | 8.0–10.5 | – | Mn ≤2.0 / Si ≤1.0 |
| 304L | ≤0.03 | 18.0–20.0 | 8.0–12.0 | – | Mn ≤2.0 / Si ≤1.0 |
| 316 | ≤0.08 | 16.0–18.0 | 10.0–14.0 | 2.0–3.0 | Mn ≤2.0 / Si ≤1.0 |
| 316L | ≤0.03 | 16.0–18.0 | 10.0–14.0 | 2.0–3.0 | Mn ≤2.0 / Si ≤1.0 |
| 321 | ≤0.08 | 17.0–19.0 | 9.0–12.0 | – | Ti ≥5×C |
| 347 | ≤0.08 | 17.0–19.0 | 9.0–13.0 | – | Nb ≥10×C |
| 410 | ≤0.15 | 11.5–13.5 | ≤0.75 | – | Mn ≤1.0 / Si ≤1.0 |
Limits vary slightly by product standard. Actual heat analysis is reported on the Material Test Certificate.
Mechanical Properties
| Grade / class | Tensile (MPa) | Yield (MPa) | Note |
|---|---|---|---|
| ISO 3506-1 A2-70 / A4-70 | 700 min | 450 min | 0.2% proof |
| ISO 3506-1 A2-80 / A4-80 | 800 min | 600 min | 0.2% proof |
| ASTM A193 B8 / B8M Cl.1 | 515 min | 205 min | Solution annealed |
| ASTM A193 B8 Cl.2 (≤¾ in) | 860 min | 690 min | Strain hardened |
| ASTM A193 B6 (410) | 760 min | 585 min | Hardened and tempered |
Minimum values per cited standards; they vary by diameter, condition and heat treatment.
Available Fastener Types
Available as bolts, nuts, screws, washers, studs and special fasteners to drawing, subject to size and standard. Browse all products.
Applications and Industries
Finishing, Quality and Packaging
Finishes such as passivation, plating, galvanizing or customer-specified treatments are selected to suit the material and service. Inspection may include dimensional, visual, mechanical and chemical checks, PMI where applicable, and Material Test Certificates (EN 10204 3.1 where requested). Goods are packed for export. See Quality.