SS 321 Hexagonal Bar
Stainless Steel 321 Hexagonal Bars are titanium-stabilized austenitic stainless steel products engineered for excellent resistance to intergranular corrosion at elevated temperatures. With a six-sided profile, these hex bars offer high strength combined with good machinability, making them ideal for high-temperature structural, exhaust, and process applications. Titanium stabilization prevents chromium carbide precipitation during welding and prolonged exposure to heat, giving SS 321 a distinct advantage over standard 304-series grades in high-temperature service.
What is SS 321 Hexagonal Bar
SS 321 Hexagonal Bars are a titanium-stabilized version of 18-8 austenitic stainless steel, developed specifically to resist sensitization when exposed to temperatures in the 425°C to 900°C range, where standard grades are prone to intergranular corrosion. The titanium in the alloy preferentially combines with carbon, keeping chromium in solid solution and preserving corrosion resistance in and near weld zones. This makes SS 321 the preferred choice for aerospace components, exhaust and boiler systems, heat exchangers, and other applications involving sustained high-temperature exposure.
Specifications of SS 321 Hexagonal Bar
| Parameter | Specification |
|---|---|
| Size Range | 6mm to 200mm |
| Length | 1m to 6m (custom cut lengths available) |
| Standards | ASTM A276, ASTM A479, ASME SA276, SA479 |
| Finish | Bright, Black, Polished, Peeled |
| Tolerance | h11, h10 as per ISO standards |
| Heat Treatment | Annealed & Pickled / Bright Annealed |
| Form | Hexagonal (6-sided bar) |
| Density | 8.0 g/cm³ |
Chemical Composition of SS 321 Hexagonal Bar
| Element | SS 321 (%) |
|---|---|
| Carbon (C) | ≤ 0.08 |
| Manganese (Mn) | ≤ 2.00 |
| Silicon (Si) | ≤ 0.75 |
| Phosphorus (P) | ≤ 0.045 |
| Sulfur (S) | ≤ 0.030 |
| Chromium (Cr) | 17.00 – 19.00 |
| Nickel (Ni) | 9.00 – 12.00 |
| Titanium (Ti) | 5x(C+N) – 0.70 |
| Nitrogen (N) | ≤ 0.10 |
| Iron (Fe) | Balance |
Mechanical Properties of SS 321 Hexagonal Bar
| Property | SS 321 |
|---|---|
| Tensile Strength (MPa) | 515 min |
| Yield Strength (0.2% offset, MPa) | 205 min |
| Elongation (%) | 40 min |
| Hardness (Brinell HB) | ≤ 217 |
| Modulus of Elasticity (GPa) | 193 |
| Melting Point (°C) | 1400 – 1425 |