An SS 321 Washer is a thin, plate-like fastener component primarily used to distribute the load of a bolt or nut evenly across the clamped surface, preventing damage and ensuring a secure connection. These washers are manufactured from Stainless Steel Grade 321, an austenitic alloy stabilized with Titanium. This element prevents the depletion of chromium at grain boundaries during exposure to high temperatures (the sensitization range, 425°C to 850°C), thereby maintaining the material’s full resistance to intergranular corrosion. Zeron Fasteners manufactures and supplies robust SS 321 Washers (including Flat, Spring, and Locking types) that are essential for critical, high-heat applications in exhaust systems, aircraft components, furnace assemblies, and petrochemical plants, where superior material integrity is required alongside mechanical performance.
| Element | Composition (%) |
|---|---|
| Carbon (C) | 0.08 |
| Manganese (Mn) | 2.00 |
| Silicon (Si) | 1.00 |
| Chromium (Cr) | 17.0 – 19.0 |
| Nickel (Ni) | 9.0 – 12.0 |
| Titanium (Ti) | 5 x C – 0.70 |
| Phosphorus (P) | 0.045 |
| Sulfur (S) | 0.030 |
Note: The Titanium content is five times the Carbon content minimum, up to a maximum of 0.70%.
| Property | Value (Typical) |
|---|---|
| Hardness (Rockwell B) | 95 |
| Material Condition | Annealed |
| Washer Type | Flat, Spring, Lock, Star |
| Dimensional Standard | ASME B18.22.1 (Flat) |
| Recommended Service Temperature | 850°C |