Higher yield than Q235 with micro-alloyed toughness — the weight-saving choice for bridges, buildings, machines and heavy structures.
STANDARD: GB/T 1591GRADE: Q355BTHICKNESS 2–100 mm
YIELD STRENGTH
≥355 MPa
TENSILE STRENGTH
470–630 MPa
IMPACT ENERGY
≥34 J @ −20°C
01 · PRODUCT OVERVIEW
Q355B is a low-alloy high-strength structural steel to GB/T 1591, micro-alloyed with niobium, vanadium and titanium. It delivers about 50 % higher yield strength than Q235B, allowing lighter sections and reduced welding, while keeping good weldability and excellent low-temperature toughness.
WHY CHOOSE Q355B
One material, one grade — Q355B only. Micro-alloyed chemistry, guaranteed 355 MPa yield, certified impact toughness and full traceability via mill certificate.
02 · KEY FEATURES
High Yield Strength
≥355 MPa yield enables thinner, lighter sections — up to ~30 % weight saving versus Q235 designs.
Excellent Weldability
Low carbon equivalent (CEV) keeps HAZ hardness low — weldable without pre-heat in most shop conditions.
Low-Temperature Toughness
Guaranteed ≥34 J at −20 °C (grade B) for safe service in cold climates and dynamic loading.
Weight Saving
Higher design stress cuts plate thickness and tonnage, reducing material, freight and fabrication cost.
Certified Quality
Mill test certificate with full chemistry and mechanicals supplied for every batch; third-party inspection available.
Cut-to-Size
Plasma and flame cutting to drawing — plates, blanks and profiled parts ready for use.
Note: Micro-alloy elements Nb, V, Ti added singly or in combination per GB/T 1591. Cu ≤ 0.40 %, N ≤ 0.012 %, Al ≥ 0.015 %. Mill test certificate supplied with every batch.
Hot-rolled, mill scale surface; shot-blasted & primed, or oiled, available on request
Custom width, length, edge preparation and profiling available — specify your requirement in the inquiry.
07 · APPLICATIONS
Steel bridges & gantry structures
Building frames & high-rise columns
Engineering machinery & cranes
Shipbuilding & marine structures
Pressure vessels & storage tanks
Wind power towers & equipamento pesado
08 · PROCESSING & PACKAGING
Flame / plasma cutting, shot blasting, edge milling and painting available. Plates packed on steel or wooden pallets, steel-banded and protected for ocean shipment.
DELIVERY
Sea freight with full export documentation (CI, PL, CO, MTC, third-party inspection if required) and loading supervision.
Need Q355B plate for your structure?
Tell us thickness, largura, length and quantity — we will confirm stock, price and delivery within 24 hours.