S355JR - 1.0045

S355JR is a structural grade steel recognized under the EN 10025-2 standard, similar to its peer S235JR but with enhanced strength.

The "S" in its designation signifies that it is meant for structural application, ensuring it efficiently supports load-bearing frameworks like buildings, bridges, and offshore structures. The "355" symbol indicates a minimum yield strength of 355 megapascals, suggesting it is more robust compared to similar grades. This makes it highly suitable for industries where higher strength is needed without excessively increasing the weight of the material. The "JR" suffix implies that the steel has passed a Charpy V-notch impact test at 20°C, guaranteeing a minimum energy absorption of 27 joules. This implies it can withstand impacts without fracturing, an essential characteristic for structures subjected to dynamic forces or movement.

Chemically, S355JR is a low-carbon, non-alloy steel. Its composition includes elements like manganese and silicon for enhanced mechanical performance and ductility. Trace amounts of nickel, chromium, and copper provide a degree of corrosion resistance, although protective coatings are advised for harsher environments to prevent rust.

One of the notable properties of S355JR is its good weldability due to its chemical composition, which makes it easy to weld without preheating — this is particularly beneficial in construction settings, where speed and safety are priorities. The blend of mechanical characteristics, including high tensile strength and excellent shaping capabilities, makes S355JR a versatile choice for general structural purposes, from simple beams in industrial facilities to complex parts in transport engineering and power production sectors.

Mechanical Properties

Chemical Properties

Applications

S355JR is a versatile structural steel grade known for its application across a range of industries.

In the construction industry, S355JR is a preferred choice for fabricating beams, columns, and trusses in buildings, thanks to its high yield strength. It is also commonly utilized in bridge construction, both for highway bridges that manage heavy traffic loads and pedestrian bridges where its impact resistance ensures safety and stability.

Additionally, it finds applications in offshore structures like oil rigs and wind turbine platforms, where its resilience against harsh environmental conditions is essential.In the field of heavy and transport engineering, S355JR is used extensively for heavy-duty equipment such as bulldozers and excavators. It is notably applied in making blades, buckets, and frames where strength and wear resistance are crucial. The steel's high strength-to-weight ratio makes it suitable for cranes and dump trucks, while in railway applications, it is used in constructing robust railway wagons.

S355JR also plays a prominent role in power engineering. It is used in power plants for structural components like support beams and frames, and in fabrication of transmission towers due to its high tensile strength and durability.

While S355JR is well-suited for a variety of demanding applications, it is not recommended for environments that require excellent corrosion resistance unless specific protective measures are taken.