S355 grade steel is a medium tensile, low carbon manganese steel which is readily weldable and possesses good impact resistance (also in sub-zero temperatures).
This material is commonly supplied in the untreated or normalised condition. Machinability is similar to that of mild steel.
This grade was first specified as the European EN10025 standard and later published by the British Standards Institute as BS EN 10025, S355, S355J2 and S355J2+N. These superseded the BS4360.
High Peak Steels stock S355 in black steel round bar.
UK Standard S355 | European Grades EN14A | 150M19
Mark Thornley, Managing Director of High Peak Steels, shares his extensive knowledge and experience with a question and answer session on S355 / EN10025 structural steel…
It’s a structural steel, conforming to the En10025 European standard. This standard superseded the old BS4360 range in 1990 and we are seeing more and more influence for complying with the European standards. The S stands for a Structural Steel, the 355 depicts the yield stress and strength. It has become more popular because of its versatility, strength, weldability and impact resistance in its raw state. It is mass produced and has many applications. Oh, and it’s great value for money.
Ibeams, columns, hollow section, angles, and flats, which are mainly structural products, but more recently manufacturers have been offering round bar because of its refined structure, excellent mechanical properties, and weldability.
S355 steel’s versatility, strength, weldability, and impact resistance make it a preferred choice for a wide range of applications across industries such as construction, engineering, manufacturing, transportation, energy, and more. Its reliability and performance characteristics have established it as a go-to material for various structural requirements.
Not a lot, chemically. It still has a similar manganese content and carbon content, but it does boast a higher yield strength to help with the pressure needed to create a permanent deformation. It boasts a higher tensile range than mild steel and is supplied with impact test results. It can be used in minus temperature applications like containers or items that end up in cold climates. It will machine the same as mild steel and is just as cost efficient.
We stock mainly solid round bar 10mm diameter right up to 500mm diameter, but because of its popularity we are extending our product range to include squares, flats, hollow sections and Ibeams. We do also offer plasma or laser cut profiles in this grade.
| Product | Min size | Max size |
|---|---|---|
 | 20mm dia | 330mm dia |
 | ||
 | ||
 |
| C | Si | Mn | S | P | Cr | Ni | Mo | |
|---|---|---|---|---|---|---|---|---|
| Min | ||||||||
| Max | 0.22 | 0.55 | 1.6 | 0.03 | 0.03 |
| Unit | Size Range mm | Yield N/mm2 | 0.2% proof N/mm2 | UTS (Rm) N/mm2 | Elong (A) % | Red of Area (Z) % | Hardness HB | Impact test (KV) J |
|---|---|---|---|---|---|---|---|---|
| Normalised (min) | S355J2+N 16mm dia | 345 | 470 | 22 | 27 | |||
| Normalised (max) | S355J2+N 40mm dia | 630 | ||||||
| Normalised (min) | S355J2+N 100mm dia | 295 | 450 | 18 | 27 | |||
| Normalised (max) | S355J2+N 150mm dia | 600 | ||||||
| Normalised (min) | S355J2G3 250mm dia | 265 | 400 | 23 | 25 | |||
| Normalised (max) | S355J2G3 500mm dia |
Not sure if EN10025 or EN14 is the best steel for the job? Explore our range of steels by material to get a better understanding of characteristics and applications.
Whatever the sector, we understand the bespoke steel requirements for each application; supplying stock lengths and cut pieces directly to your factory.
Alongside steel supply, we offer a range of steel stockholder services, including bar turning, sawing and precision grinding. We also provide steel hardening and tempering treatments.
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