Standard and edition
Confirm the controlling document; a grade name or cross-reference alone is not a complete acceptance specification.
Carbon Steel Round Bar
Carbon Steel AISI 1045 / C45 Round Bar Manufacturer, Exporter and Supplier
AISI 1045 / C45 is a medium-carbon steel round bar used for shafts, gears, axles and machined parts. Its higher carbon content allows greater hardness and strength after suitable heat treatment.
These bars may be supplied hot rolled, normalized, annealed or quenched and tempered, depending on the specification. When ordering, mention the grade, diameter, length, finish and required condition. You can also compare AISI 1018 round bar where easier forming is needed.
At a glance
Carbon Steel AISI 1045 / C45 Round Bar quick facts
- Product
- Carbon Steel AISI 1045 / C45 Round Bar
- Material category
- Carbon Steel Round Bar
- Product reference
- Carbon Steel AISI 1045 / C45 Round Bar
- Standards and designations referenced
- UNS G10450; EN C45 / 1.0503; SAE 1045
- Enquiry details
- Grade, dimensions and supply condition
Confirm the applicable specification and availability for your required size and condition.
Buyer selection guide
How to select Carbon Steel AISI 1045 / C45 Round Bar
Begin with the drawing, equipment specification, or governing code. The product name identifies the material route; acceptance depends on the complete purchase specification.
Material identityState Carbon Steel AISI 1045 / C45 and any required designation.
Governing standardConfirm the appropriate bar specification, such as ASTM A29/A29M for general bar requirements, and the required grade and edition.
Dimensions and conditionProvide diameter, length, quantity, tolerance, condition, finish, and machining allowance.
VerificationDefine testing, inspection, marking, traceability, documentation, destination, and timing.
Common applications
Applications of Carbon Steel AISI 1045 / C45 Round Bar
AISI 1045 round bar is used where machined parts need moderate to high strength and the option of heat treatment. It is commonly selected for shafts, axles, gears, pins, couplings and mechanical components. The required condition depends on the load, wear and working environment.
For parts exposed to rubbing or wear, surface hardening may be suitable. For parts needing more accurate dimensions, a bright finished bar may be considered. Confirm hardness and dimensional tolerances before machining.
Specifications
AISI 1045 / C45 Round Bar Specifications
The final specification depends on the intended use and supply condition. State the exact grade and product standard on the purchase order.
| Requirement | Details |
|---|---|
| Material | AISI / SAE 1045, UNS G10450; C45 is a closely related EN grade, not an automatic substitute in every specification |
| Bar requirements | ASTM A29/A29M (general requirements); ASTM A576 or ASTM A108 where applicable to the ordered product form |
| Form | Round bar; other forms subject to confirmation |
| Supply condition | Hot rolled, normalized, annealed, cold finished or quenched and tempered, as specified |
| Surface finish | Black, peeled, turned, ground or bright finished, as ordered |
| Dimensions | Confirm diameter, length, straightness and machining allowance with the supplier |
| Tolerance | Specify the required tolerance class and standard; do not assume a fixed h9 or h11 tolerance |
| Documents | Mill test certificate, chemical analysis, mechanical test data and traceability as agreed |
The size and condition of an available bar should be confirmed before placing an order. Avoid using one mechanical property value for every diameter or treatment.
Chemical composition
Chemical Composition of AISI 1045 Round Bar
The following heat-analysis limits are commonly listed for SAE/AISI 1045 carbon steel under ASTM A29/A29M. Values are percentages by weight. C45 has its own limits under applicable EN requirements.
| Element | AISI 1045 composition (wt. %) |
|---|---|
| Carbon (C) | 0.43–0.50 |
| Manganese (Mn) | 0.60–0.90 |
| Phosphorus (P) | 0.040 max |
| Sulfur (S) | 0.050 max |
| Iron (Fe) | Balance |
Silicon limits and additional chemistry requirements depend on the selected product specification. Confirm the supplied heat analysis using the mill test certificate.
Mechanical properties
Mechanical Properties of AISI 1045 / C45 Round Bar
Mechanical properties change with the bar diameter, finishing process and heat-treatment condition. The table below shows reference values for C45 (1.0503) in the quenched and tempered condition. They are not guaranteed values for every AISI 1045 bar.
| Bar diameter | 0.2% proof strength | Tensile strength | Elongation |
|---|---|---|---|
| Under 16 mm | 490 MPa min | 700–850 MPa | 14% min |
| Over 16 to 40 mm | 430 MPa min | 650–800 MPa | 16% min |
| Over 40 to 100 mm | 370 MPa min | 630–780 MPa | 17% min |
Reference: published C45 (1.0503) quenched-and-tempered product data. Specify the actual material standard and heat treatment to establish acceptance limits. For general reference, steel density is approximately 7.85 g/cm³.
Do not apply these values to annealed, as-rolled or cold-drawn bars without checking the relevant specification and certificate.
Technical considerations
What to verify before specifying Carbon Steel AISI 1045 / C45 Round Bar
Product condition
Check that property values apply to the required diameter, heat treatment, test direction and temperature.
Dimensions and finish
State tolerances, straightness, length, surface finish, machining allowance, and end condition where required.
Evidence and traceability
Define inspection, test reports, marking, heat identification, third-party requirements, and destination documentation.
Designations
AISI 1045 / C45 Grade Designations
| System | Grade or designation |
|---|---|
| SAE / AISI | 1045 |
| UNS | G10450 |
| EN / DIN | C45 / 1.0503 |
| Common German designation | C45E / 1.1191 (different specified chemistry and quality requirements may apply) |
| JIS | S45C (similar grade, confirm specification before substitution) |
Grade designations can have different chemical limits, cleanliness requirements and mechanical acceptance rules. Do not substitute a similar designation without approval.
More about the material
More About Carbon Steel AISI 1045 / C45 Round Bar
Surface Finish and Bar Conditions
AISI 1045 round bars can be supplied with hot rolled, peeled, turned or ground finishes. The finish affects surface quality, dimensional accuracy and how much machining is needed. Buyers should choose the finish based on the final part. The hot rolled round bar page explains this common starting form.
Machining Allowance and Dimensional Requirements
Round bars used for shafts, pins and other machined parts may need extra material for turning or grinding. The allowance depends on the starting diameter, surface condition and finished size. Straightness and diameter tolerance should also be agreed before ordering. Use the round bar weight calculator to estimate the starting material weight.
Material Inspection and Traceability
Material test certificates may be required to confirm the steel grade and the test results for a supplied batch. Depending on the order, these can include chemical analysis, mechanical test results and heat-number identification. Buyers should state the certificate type, marking and any extra inspection requirements when ordering. See the quality assurance information for more about inspection and documentation.
Product questions
Carbon Steel AISI 1045 / C45 Round Bar FAQ
Is AISI 1045 the same as C45?
They are closely related medium-carbon grades, but their standard requirements and chemical limits may differ. Check the drawing and purchase specification before treating them as interchangeable.
Can AISI 1045 round bar be hardened?
Yes. AISI 1045 can be hardened and tempered, and surface hardening may be used for suitable components. The result depends on size and the treatment process.
What is the difference between hot rolled and bright AISI 1045 bars?
Hot rolled bars normally have an as-rolled surface. Bright or cold-finished bars can offer a cleaner finish and closer dimensions, depending on the process.
Is AISI 1045 suitable for welding?
Welding is possible, but it often requires more care than lower-carbon steel. Preheating and controlled cooling may be needed, depending on part thickness and the welding procedure.
Can I request a mill test certificate for AISI 1045 bar?
You can specify the required mill test certificate, chemistry, mechanical tests and heat-number traceability when sending an enquiry.
What information should I provide for an AISI 1045 quotation?
Send the grade, standard, diameter, length, quantity, supply condition, finish, tolerance, inspection requirements and delivery destination.