
Carbon Steel Square Bar
Specify Q235B, Q355B, SAE 1018, SAE 1045 or your contract grade for general fabrication and machining requirements. Size and delivery condition follow your enquiry.
Explore Carbon Steel BarCarbon Steel · Stainless Steel · Alloy Steel · Solid Square Section
Source solid square steel bars for your machining, fabrication and distributor orders. Share the material grade, side length, bar length, quantity and destination port for an accurate quotation.
Choose a material grade ↓
Choose carbon, stainless or alloy steel by the drawing, grade standard and finished-part requirements.

Specify Q235B, Q355B, SAE 1018, SAE 1045 or your contract grade for general fabrication and machining requirements. Size and delivery condition follow your enquiry.
Explore Carbon Steel Bar ↗
Request 304 or 316L square bars for fabricated fittings, equipment parts and corrosion-resistant components. Confirm the finish and applicable material certificate.
Explore Stainless Steel Bar ↗Send the grade, side size, delivery condition and order tonnage for a 4140 or other alloy steel supply review.
Order by the square section side length, not a round diameter or tube outside dimension. Specify the material standard and tolerance for each item.
| Cross-section | Solid square steel bar with four equal sides |
| Primary size | Square side length (a × a), specified in mm or inches |
| Steel grades | Carbon steel Q235B, Q355B, SAE 1018 / 1045; stainless steel 304 / 316L; alloy steel by enquiry |
| Cold-finished carbon / alloy | ASTM A108-24, where applicable |
| Hot-wrought carbon / alloy | ASTM A29/A29M-26 general requirements, with an applicable individual grade specification |
| Stainless steel bars | ASTM A276/A276M-25, including square bar forms |
| Hot-rolled square dimensions | EN 10059:2003 or agreed dimensional tolerance standard |
| GB square bar dimensions | Applicable GB/T 702 edition specified with your purchase order |
| Finish / delivery | Hot-rolled, cold-drawn or bright-finished as applicable to the material and size |
| Length | Mill length or cut lengths confirmed with your order |
| Inspection documentation | Heat analysis, dimensional checks, mechanical tests and MTC as specified |
Use the solid square section width a as your ordering dimension. Reference weights below help estimate logistics tonnage.
| Side (mm) | Carbon steel kg/m | 316L steel kg/m |
|---|---|---|
| 10 × 10 | 0.785 | 0.800 |
| 12 × 12 | 1.130 | 1.152 |
| 16 × 16 | 2.010 | 2.048 |
| 20 × 20 | 3.140 | 3.200 |
| 25 × 25 | 4.906 | 5.000 |
| 30 × 30 | 7.065 | 7.200 |
| 40 × 40 | 12.560 | 12.800 |
| 50 × 50 | 19.625 | 20.000 |
Illustrative theoretical weights based on nominal solid squares: carbon steel 7,850 kg/m³ and 316L stainless steel 8,000 kg/m³. The sizes shown are calculation examples; actual availability is confirmed per order.
The full section area is side × side. Use this section for your weight estimate and grade-specific dimensional inspection.

The full-metal cross-section and corners remain visible in genuine product photography.
A solid square bar has metal across the entire cross-section. A square hollow tube has a cavity and specified wall thickness. Choose the profile listed on your project drawing.
View Square & Rectangular Steel Tube ↗Surface finish, corner condition and dimensional tolerance vary by the material grade and manufacturing route.

A refined dimensional finish for cutting, fabrication and machining blanks.
Natural mill finish with dimensions and corner radius controlled by the specified hot-rolled product tolerance standard.
Request the nominal size, edge tolerance and straightness required by your application.
Request a smooth finished surface and a defined dimensional class for your machining or assembly process.
Final size and surface condition are confirmed by grade and available manufacturing route.
Solid square sections provide convenient stock for fabricated parts, machined blanks and steelwork fittings.

Square bar blanks for fabricated machine fixtures and mechanical components.
Cut bar stock for keys, blocks and power-transmission parts where the drawing specifies a square profile.
Square steel parts for equipment support brackets and steelwork connections.
Solid square sections for cutting, drilling and industrial stockholding.
Steel square blanks for jigs, fixture bars and mounting parts.
Machining stock for keyed assemblies and precision-cut components.
Square profiles for specialist fittings and fabricated hardware.
Solid bar components for structural brackets and support assemblies.
Stainless square bars for assemblies requiring a corrosion-resistant grade.
Repeat grade and section orders for bar distributors and stockists.
Bring together steel manufacturing scale, company-wide inventory, material certification and export order coordination.
Company-wide steel output supports regular steel procurement and project-based sourcing.
Manufacturing ↗Our company-wide stock supports supply planning. Current square bar sizes and materials are checked against your list.
Steel Inventory ↗Specify the material, side-size class, surface condition and inspection documents for your order.
Quality Control ↗Combine grades, section sizes, quantities, port and delivery terms in one quotation request.
Estimate theoretical weight using side length, bar length and selected nominal material density.
Weight = side² × length × density. This estimate uses nominal full-section dimensions; final delivered weight depends on the agreed size tolerances and commercial terms.

BAOSTEEL METAL supports industrial procurement with 8 million metric tons of actual annual steel production across its product range. Send your square bar schedule so our team can confirm material supply and delivery arrangements.
Share the material grade, side dimension and finished length to review current square bar availability and production options. Our company-wide steel inventory totals approximately 1 million metric tons across categories.


Include your side-size tolerance, squareness, straightness, surface condition and test certificate requirements in the enquiry.
Add your drawings, cut lengths and machining allowances to the purchase enquiry. Our team can confirm available saw cutting, drilling, chamfering and preparation arrangements against the ordered grade and section.

Confirm bundled quantity, bar length, total shipping weight and destination port with your RFQ. Your order can specify suitable bundling, protection and export documentation.
Continue to the relevant steel bar product and compare the material standard, section shape and fabrication requirements.
The ordering details buyers commonly confirm before purchasing solid square bars.
Share the square side length, material grade, finished bar length, quantity, tolerance requirements and destination port.
A square bar is ordered by its external side length. The nominal cross-section area equals side length squared.
Multiply side length in millimetres by itself, multiply by length in metres and by 0.00785 to estimate carbon steel kilograms per bar.
Choose the material specification first, such as ASTM A108 for applicable cold-finished carbon bar or ASTM A276 for stainless bars. Add the square-section size and tolerance standard to your RFQ.
Include the required lengths, drawings, MTC and dimensional inspection conditions with your enquiry to receive an order-specific quotation.
Send your required grade, dimensions, quantity and destination. Our team will review the inquiry.