Q235 hot-rolled steel plate is a widely used carbon structural steel product, renowned for its excellent comprehensive mechanical properties, good plasticity, and weldability. As a fundamental material in construction and general engineering, it meets the Chinese standard GB/T 700-2006.

The name "Q235" is derived from its mechanical properties:

"Q" stands for Yield Strength (Qu fu dian).

"235" indicates the minimum yield strength of 235 MPa (Megapascals) for steel sections ≤ 16mm thick.

This steel is considered a mild or low-carbon steel, making it highly versatile and easy to fabricate.

Key Characteristics & Properties

Excellent Strength and Ductility: Q235 offers a good balance between strength (Yield Strength: ≥235 MPa, Tensile Strength: 370-500 MPa) and ductility (Elongation: ≥26%). This allows it to withstand significant deformation before failure, which is crucial for absorbing energy in structural applications.

Good Weldability and Formability: Due to its low carbon content, Q235 can be easily welded using all standard methods without pre-heating or post-heat treatment in most cases. It can also be readily cold-worked, bent, sheared, and punched into desired shapes.

Cost-Effectiveness: As one of the most common and widely produced steel grades in China, Q235 is highly economical, offering reliable performance at a competitive price point.

Hot-Rolled Process: The hot-rolling manufacturing process involves shaping the steel at high temperatures (above its recrystallization point). This results in a product with a characteristic mill scale surface and slightly rounded edges. The process improves the steel's toughness and workability but offers less precise dimensional tolerances compared to cold-rolled steel.

Common Applications

Q235 Hot-rolled steel plate is a workhorse material across numerous industries:

Construction: Structural frames, beams, columns, and reinforcement parts in buildings and bridges.

Manufacturing: Base plates, machine frames, brackets, and various machinery components that do not require high-strength alloys.

Automotive: Chassis components, truck frames, and brackets.

General Fabrication: Welded structures, storage tanks, shelves, and guards.

Shipbuilding: Used for non-critical structural parts in shipbuilding.

Comparable International Grades

While not exactly equivalent, Q235 is often compared to these international grades:

ASTM A36 (USA): The most common comparison. Both are general-purpose structural steels with similar yield strength.

S235JR (EN 10025-2 Europe): A European non-alloy structural steel with a 235 MPa minimum yield strength.

SS400 (JIS G 3101 Japan): A Japanese structural steel, though its standard is based on tensile strength.

Note: Direct substitution requires careful consideration of the specific standard's requirements for chemistry, deoxidation practices, and guaranteed properties.

Advantages at a Glance

High Versatility: Suitable for a vast range of applications.

Ease of Fabrication: Easy to weld, cut, and form.

Economic Efficiency: Provides excellent value for money.

Wide Availability: Readily available in various sizes and thicknesses globally.