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Carbon Steel Flat Bar is manufactured with excellent dimensional accuracy, reliable mechanical strength, and good fabrication performance. It is widely used for structural components, machinery, fabrication, and general engineering projects requiring durable and cost-effective steel materials.
Suitable for welding, cutting, drilling, and machining, carbon steel flat bars provide dependable performance for construction, industrial manufacturing, and OEM fabrication.
Carbon steel flat bar (solid rectangular steel strip stock, hot rolled structural flat bar, cold drawn precision bright flat steel, A36 mild steel flat plate bar, and 1045 high-strength carbon steel section) is manufactured through continuous hot rolling, slit sheet processing, or precision cold drawing to deliver highly uniform rectangular solid metal profiles. Engineered for structural steel fabrication, building gratings, industrial machinery brackets, conveyor side guides, trailer frames, and ornamental ironwork, carbon steel flat bar provides excellent shear strength, high dimensional stability, predictable bendability, and superior arc welding performance.
At XQJ Metal, we operate advanced structural steel rolling lines, precision cold drawing benches, automatic hydraulic shearing machines, and edge-rounding processors to supply premier carbon steel flat bar products conforming strictly to global metallurgical standards, including ASTM A36 (carbon structural steel), ASTM A108 (cold-finished carbon steel bars), EN 10025 (S235JR / S275JR / S355JR), JIS G3101 (SS400 / SM490), and GB/T 704 specifications. We offer complete width ranges from 12mm to 150mm (1/2 inch to 6 inches), thickness options from 3mm to 25mm (1/8 inch to 1 inch), standard 6m / 12m length bundles, and custom cut-to-length flat steel profiles in raw mill scale, bright cold drawn, red oxide primed, or hot-dip galvanized surface finishes.
| Steel Grade & Designation | Standard Compliance | Width Range (mm / inch) | Thickness Range (mm / inch) | Yield Strength (MPa) | Primary Engineering Applications |
| ASTM A36 / Q235B | ASTM A36 / GB/T 700 / EN S235JR | 12mm to 150mm (1/2″ – 6″) | 3mm to 25mm (1/8″ – 1″) | ≥ 250 MPa | General structural welding, base plates, building brackets, steel grating bars & walkways |
| AISI 1018 / S275JR | ASTM A108 / EN 10025-2 | 150mm to 100mm (5/8″ – 4″) | 3mm to 20mm (1/8″ – 3/4″) | ≥ 370 MPa (Cold Drawn) | Cold forming, carburized machine parts, hinge plates & automated manufacturing fixtures |
| AISI 1045 / C45 / S45C | ASTM A29 / JIS G4051 / GB Q355B | 20mm to 120mm (3/4″ – 4-3/4″) | 5mm to 25mm (3/16″ – 1″) | ≥ 345 to 540 MPa | Medium-carbon wear plates, machinery rails, drive keys, guide bars & structural stiffeners |
| ASTM A572 Gr.50 / S355JR | ASTM A572 / EN 10025-2 | 25mm to 150mm (1″ – 6″) | 6mm to 25mm (1/4″ – 1″) | ≥ 355 MPa | Heavy-duty structural framing, bridge stiffeners, trailer chassis & mining equipment supports |
Selecting the appropriate production method for carbon steel flat bar depends on dimensional tolerance requirements, surface finish expectations, and secondary machining plans:
To support modular assembly and speed up jobsite installation, XQJ Metal provides comprehensive value-added processing services for carbon steel flat bar orders:
Our durable carbon steel flat bar profiles serve as versatile structural building blocks across a vast array of global engineering industries:
To guarantee complete chemical purity, consistent mechanical properties, and perfect straightness, XQJ Metal enforces strict Quality Assurance (QA) protocols on every carbon steel flat bar batch:
Q1: What is the main difference between A36 and 1045 carbon steel flat bar?
A: ASTM A36 is a low-carbon steel with excellent weldability and ductility, making it ideal for general welding and structural framing. AISI 1045 is a medium-carbon steel with higher tensile strength and hardness that can be heat-treated, making it suitable for wear plates, machinery rails, and stressed mechanical components.
Q2: Can XQJ Metal provide hot-dip galvanized carbon steel flat bar for outdoor grating and handrails?
A: Yes, we supply hot-dip galvanizing according to ASTM A123, providing a heavy zinc coating of 60µm–85µm (450g/m²–600g/m²) to ensure over 25 years of corrosion-free service in outdoor and industrial environments.
To request live FOB/CIF spot quotes, weight calculation tables, or steel sample pieces for carbon steel flat bar, Contact Our Steel Engineering Team today.
Our materials support a wide range of construction and infrastructure projects
Carbon steel flat bar is supplied in fixed widths and thicknesses with a rectangular profile, making it suitable for structural fabrication and machined components. Steel plate is typically available in larger dimensions and is commonly selected for heavy-duty structural and pressure-related applications.
Carbon steel flat bar is easy to cut, weld, drill, and machine, helping manufacturers reduce processing time and material waste. Its consistent dimensions make it well suited for efficient fabrication in construction, machinery, and industrial projects.
Carbon steel flat bar is widely used to manufacture support brackets, base plates, frames, mounting plates, reinforcement members, machine components, and other fabricated structural parts requiring reliable strength and straightforward processing.
It offers excellent resistance to seawater corrosion and maintains strength in humid and salt-rich conditions.
No. Strength is achieved through strain hardening rather than heat treatment.
Yes. It provides excellent weldability for structural fabrication.
Yes, it is commonly applied in tanks and pressure equipment.
Yes. It provides higher strength compared with most non-heat-treated aluminum alloys.
Yes. Thickness, width and temper can be adjusted based on project demand.
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