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Carbon Steel Hex Bar offers excellent mechanical strength, dimensional accuracy, and machining performance, making it ideal for precision manufacturing and industrial applications. Its hexagonal profile provides secure clamping during machining and improves processing efficiency.
Widely used for fasteners, shafts, mechanical components, precision parts, and OEM manufacturing requiring reliable performance and excellent machinability.
Carbon steel hex bar (high-precision hexagonal steel rod, cold drawn 1215 free-machining hex bar, 12L14 leaded steel hex stock, 1018 low carbon hexagonal bar, 1045 medium carbon steel hex bar, and bright finished structural hex bar) is manufactured through precision hydraulic cold drawing or cold rolling to produce solid hexagonal-profile steel bars with exact flat-to-flat dimensions. Engineered for high-speed automatic CNC screw machining, precision hydraulic hose fittings, threaded fasteners, nuts, valves, and automotive sockets, carbon steel hex bar provides exceptional wrench-grip clamping, superior dimensional tolerance, outstanding chip-breaking machinability, and reliable core strength.
At XQJ Metal, we operate advanced cold drawing benches, centerless polishing machines, automatic multi-spindle straighteners, and heat-treatment furnaces to manufacture world-class carbon steel hex bar products conforming strictly to global metallurgy standards, including ASTM A108 (cold-finished steel bars), ASTM A29 (general requirements for carbon steel bars), EN 10087 (free cutting steels), JIS G4051 (S20C/S45C), and DIN 1651 specifications. We supply full flat-to-flat size options from 6mm to 100mm (1/4″ to 4″), standard mill lengths from 3m to 6m, and custom cut-to-length hexagonal steel profiles in bright cold drawn, chamfered end, and rust-inhibited surface finishes.
| Steel Grade Family | Standard Designation & UNS Code | Tensile Strength (MPa) | Yield Strength (MPa) | Hardness (HBW / HRB) | Primary Engineering Attributes |
| Free-Machining Steel | AISI 1215 / UNS G12150 / EN 11SMn30 / 9SMn28 | 380 to 520 MPa | ≥ 290 MPa | 120 to 160 HBW | Ultra-high cutting speed, superb chip breaking, ideal for high-volume automatic CNC lathe components |
| Leaded Free-Cutting | AISI 12L14 / UNS G12144 / EN 11SMnPb30 | 390 to 540 MPa | ≥ 300 MPa | 121 to 165 HBW | Maximum machinability rating (190% of 1212), extends tool life, perfect for intricate hydraulic valve fittings |
| Low Carbon Structural | AISI 1018 / ASTM A36 / Q235B / EN S235JR | 440 to 580 MPa | ≥ 370 MPa | 126 to 170 HBW | Excellent weldability and cold heading capability, suitable for custom bolts, tie rods & structural pins |
| Medium Carbon Engineering | AISI 1045 / C45 / JIS S45C / Q355B | 570 to 700 MPa | ≥ 345 MPa | 160 to 220 HBW | High fatigue strength, heat-treatable for induction-hardened hex sockets, gears, shafts & couplings |
Utilizing high-precision cold drawn processing for carbon steel hex bar ensures significant manufacturing advantages for high-speed automated machining shops:
Automotive parts suppliers, hydraulic valve manufacturers, and fastener distributors depend on our customized carbon steel hex bar value-added processing services:
Our cold finished carbon steel hex bar stock serves as a crucial engineering material across high-precision global manufacturing sectors:
To guarantee complete chemical purity, zero surface seams, and perfect dimensional uniformity, XQJ Metal enforces strict Quality Assurance (QA) protocols on every carbon steel hex bar shipment:
Q1: What is the main advantage of using 1215 or 12L14 carbon steel hex bar for CNC machining?
A: 1215 and 12L14 are free-machining steel grades containing controlled sulfur, phosphorus (and lead in 12L14) that break metal chips into small pieces during turning. This allows up to 100% faster machining speeds, extends cutting tool life, and produces superior surface finishes on hex nuts and fittings.
Q2: Can XQJ Metal supply carbon steel hex bar in both metric and fractional inch size dimensions?
A: Yes, we furnish metric hex sizes across flats from 6mm to 100mm and inch hex sizes from 1/4″ to 4″ (e.g., 7/16″, 1/2″, 3/4″, 1-1/8″, 1-1/2″, 2″) with custom length options.
To request current FOB/CIF spot price quotes, steel grade chemical datasheets, or physical sample bars for carbon steel hex bar, Contact Our Steel Engineering Team today.
Our materials support a wide range of construction and infrastructure projects
Carbon steel hex bars provide six flat surfaces that offer better grip during machining and fastening operations. They are easier to clamp in lathes, CNC machines, and automatic screw machines, making them a preferred choice for manufacturing bolts, nuts, shafts, fittings, and precision mechanical components.
Carbon steel hex bars are widely used in fastener manufacturing, machinery production, automotive components, industrial equipment, agricultural machinery, and general engineering applications. Their dimensional accuracy and excellent machinability make them suitable for both standard parts and custom-machined components.
Yes. Carbon steel hex bars can be supplied in a wide range of sizes, lengths, and grades to meet different project requirements. Additional processing services such as cutting, chamfering, machining, and custom packaging are also available to support OEM production and international export.
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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