Q355 Steel Grade Introduction and Key Features

Q355 is a high-strength low-alloy structural steel widely adopted in modern engineering. The “Q” stands for yield strength, and “355” indicates a minimum yield strength of 355 MPa. Compared to Q235, Q355 offers higher strength while maintaining good toughness and weldability.

Chemically, Q355 contains low carbon and higher levels of manganese, with micro-alloying elements such as Nb, V, and Ti. These elements refine the grain structure and significantly improve mechanical properties without compromising weldability.

Q355 can be delivered in hot-rolled, normalized, or thermomechanical controlled rolled (TMCP) conditions. TMCP plates have excellent strength-to-weight ratios and improved toughness.

Q355 is widely used in large buildings, bridges, cranes, offshore structures, heavy machinery frames, and wind power equipment. Its high strength allows designers to reduce steel consumption while ensuring safety.