Hot-rolled carbon steel sheet is a flat steel product made from carbon steel at a recrystallization temperature (usually above 900°C). It has a carbon content of ≤0.25% (low-carbon steel). Its thickness ranges from 0.35-200mm. While it has an oxide scale on the surface, it possesses high ductility and is widely used in structural components for automobiles, bridges, etc.

Main Characteristics

Processing Advantages: High-temperature rolling reduces energy consumption, suitable for large-size production.

Performance Characteristics: Compressive strength 390-422MPa, high temperature resistance, and excellent weldability.

Surface Treatment: Requires pickling to remove oxide scale; surface finish is lower than cold-rolled sheet.

Cold-rolled carbon steel sheets are steel products made from hot-rolled steel coils, which are pickled to remove oxide scale and then rolled at room temperature. They are characterized by a smooth surface, high dimensional accuracy, and high strength and hardness.

Key Properties of SS400 Steel:
Good Strength: Its 400 MPa minimum tensile strength makes it suitable for structural applications.
Excellent Weldability: Its low carbon content makes it very easy to weld using all common methods (SMAW, GMAW, FCAW, etc.) without requiring pre-heating in most cases.
Good Formability: It can be bent and shaped relatively easily, though this becomes more difficult with increasing thickness.
High Ductility: It can undergo significant deformation before fracturing, which is a key safety feature in structures.
Low Cost: It is an economical choice for large-scale construction projects.
No Corrosion Resistance: It will rust quickly if exposed to moisture.

A36 hot-rolled plate is the backbone of modern construction and heavy industry.
Building and Bridge Construction: I-beams, columns, base plates, gusset plates, and girders.
Heavy Equipment and Machinery: Frames, booms, buckets, and supports for agricultural, mining, and construction machinery.
Shipbuilding and Barge Construction: Hull plates, decks, and structural members.
Truck Frames and Trailers: Long members and crossmembers.
General Fabrication: For any project requiring a strong, weldable, and affordable steel. This includes everything from custom machine bases and welding tables to sculpture and architectural features (where the rustic "hot-rolled" look is desired).

Q195: This is the grade designation, following the Chinese GB standard (very common internationally).
Key Characteristic: Its primary advantage is low cost and high strength. Its main drawback is that it will rust (corrode) readily when exposed to moisture and oxygen unless it is protected (e.g., by painting, galvanizing, or coating).
Q195 1.2mm sheet is ubiquitous in manufacturing due to its low cost and ease of use. It is almost always used as a base material that will be painted, coated, or galvanized.
General Fabrication: Brackets, boxes, enclosures, and frames.
Automotive: Non-structural body panels, brackets, and interior parts (before rust-proofing and painting).
Furniture: Bed frames, cabinet bodies, shelving brackets.
Appliances: Housings for dryers, washing machines, and other white goods that are subsequently painted.
Ductwork and Ventilation: For HVAC systems.
Base Material for Galvanizing: This sheet is often sent through a hot-dip or electro-galvanizing process to become

Cold-rolled carbon steel plate is primarily made of two types of materials: low-carbon steel and high-quality carbon structural steel. Common grades include Q195, Q235, SPCC, and ST12. Thickness is typically less than 4 mm.
Common Materials
‌Q195/Q235‌: Common carbon structural steel with excellent cold bending and welding properties, suitable for mechanical parts, containers, and more.
‌SPCC/ST12‌: Cold-rolled carbon steel plate according to the Japanese JIS standard. SPCC is commercial steel, while ST12 is a common steel grade with similar mechanical properties.
‌DC01-DC06‌: Indicates stamping-grade steel plates of varying hardness. DC03 and above are suitable for deep drawing (e.g., automotive fuel tanks).