Stainless Steel Hexagonal Bars
ULAMEX supplies stainless steel hexagonal bars (hex bars) to industrial buyers, precision machining workshops, and fastener manufacturers across Europe. Our standard programme covers grade 1.4301 (AISI 304) – the most widely specified austenitic stainless steel for hexagonal bar stock – manufactured to EN 10088-3 and supplied in across-flats dimensions from SW 10 to SW 46 mm. Stainless steel hex bars combine excellent corrosion resistance with the six-sided geometry required for wrench-driven components, CNC-machined precision parts, and structural fastener blanks. All bars are available from stock in 6,000 mm standard lengths, with cutting to size and mill test certificate 3.1 per EN 10204 on request.
Material Properties
Our stainless steel hexagonal bars are produced in grade X5CrNi18-10 (Werkstoff 1.4301 / AISI 304), the industry-standard austenitic chromium-nickel steel that delivers a balanced combination of mechanical strength, corrosion resistance, and machinability. This grade belongs to the V2A family and is the most commonly specified stainless steel worldwide for semi-finished bar products.
Chemical Composition (per EN 10088-3)
| Element | C | Cr | Ni | Mn | Si | P | S | N |
|---|---|---|---|---|---|---|---|---|
| Content (%) | ≤ 0.07 | 17.5 – 19.5 | 8.0 – 10.5 | ≤ 2.0 | ≤ 1.0 | ≤ 0.045 | ≤ 0.015 | ≤ 0.11 |
Mechanical Properties (hot rolled condition)
| Property | Value | Standard |
|---|---|---|
| Tensile strength (Rm) | 500 – 700 MPa | EN 10088-3 |
| Proof stress (Rp0.2) | ≥ 190 MPa | EN 10088-3 |
| Elongation at break (A5) | ≥ 45 % | EN 10088-3 |
| Hardness | ≤ 215 HB | EN 10088-3 |
| Density | 7.93 kg/dm³ | — |
| Thermal conductivity | 15 W/(m·K) at 20 °C | — |
The chromium content of 17.5–19.5 % forms a self-healing passive oxide layer that provides excellent resistance to atmospheric corrosion, water, steam, weak organic acids, and many alkaline solutions. The nickel content of 8.0–10.5 % stabilises the austenitic microstructure, ensuring the material remains non-magnetic and ductile even at sub-zero temperatures. Grade 1.4301 is readily weldable using standard TIG/MIG methods and is suitable for post-weld passivation without the need for heat treatment.
For machining applications, 1.4301 hexagonal bar offers good machinability when appropriate cutting parameters are applied — carbide tooling with positive rake angles, moderate cutting speeds (120–180 m/min), and continuous chip flow. Where higher chip-removal rates are critical (e.g., automatic lathe production of hex bolts), consider the free-machining grade 1.4305 (AISI 303), which offers 30–50 % improved machinability at the trade-off of reduced corrosion resistance. Grade 1.4305 hexagonal bars are available on request — please specify when enquiring.
Available Dimensions
ULAMEX stocks stainless steel hexagonal bars in grade 1.4301 across the following across-flats dimensions. All sizes are supplied in 6,000 mm standard lengths, with cutting to your required length available on request.
| SW (across flats) | Equivalent ∅ (circumscribed circle) | Weight (kg/m) | Stock status |
|---|---|---|---|
| 10 mm | 11.5 mm | 0.69 | Stock |
| 12 mm | 13.9 mm | 0.99 | Stock |
| 14 mm | 16.2 mm | 1.35 | Stock |
| 17 mm | 19.6 mm | 1.99 | Stock |
| 19 mm | 21.9 mm | 2.49 | Stock |
| 22 mm | 25.4 mm | 3.33 | Stock |
| 24 mm | 27.7 mm | 3.97 | Stock |
| 27 mm | 31.2 mm | 5.02 | Stock |
| 30 mm | 34.6 mm | 6.20 | Stock |
| 32 mm | 36.9 mm | 7.05 | Stock |
| 36 mm | 41.6 mm | 8.93 | Stock |
| 41 mm | 47.3 mm | 11.58 | Stock |
| 46 mm | 53.1 mm | 14.58 | Stock |