AISI 4130
Alloy Steel AISI 4130
AISI 4130 alloy steel is a chromium-molybdenum low-alloy steel known for its combination of strength, toughness, hardenability and weldability when appropriate fabrication procedures are followed. Commonly known as Chromoly 4130, it is used in mechanical engineering, oil and gas equipment, energy systems and specialized industrial components.
AISI 4130 can be supplied in different product forms and heat-treatment conditions to meet specific engineering requirements. Its final mechanical properties depend on the manufacturing process, section size, heat treatment and applicable product specification.
Emirerri Steel supports industrial buyers sourcing AISI 4130 alloy steel according to required dimensions, product forms, technical specifications and availability.
Key Features
Chromium-molybdenum composition: Provides alloying characteristics suitable for demanding mechanical applications.
Good strength-to-weight potential: Suitable for components where strength and weight must be balanced through appropriate design.
Heat-treatment capability: Mechanical properties can be adjusted through suitable heat-treatment processes.
Toughness: Can provide a useful combination of strength and toughness in the specified material condition.
Weldability: Can be welded using qualified procedures appropriate to the material condition and component thickness.
Machinability: Can be machined using suitable tools and cutting parameters.
Industrial versatility: Used in mechanical, energy, transportation and oil and gas applications.
Specifications
| Parameter | Description |
|---|---|
| Grade | AISI 4130 |
| Common name | Chromoly 4130 |
| Material family | Low-alloy chromium-molybdenum steel |
| Product forms | Bars, plates, sheets, tubes and forgings, subject to availability |
| Heat-treatment options | Annealed, normalized, quenched and tempered, as specified |
| Mechanical properties | Depend on product form and material condition |
| Typical applications | Mechanical components, energy equipment and industrial engineering |
| Inspection | According to the applicable product specification |
| Certification | Material test certificate, subject to order requirements |
Important: AISI 4130 identifies the steel grade but does not, by itself, define every product requirement. The applicable manufacturing standard, dimensions, delivery condition, heat treatment and inspection requirements should be specified when ordering.
AISI 4130 – Chemical Composition
| Element | Composition (%) |
|---|---|
| Carbon (C) | 0.28–0.33 |
| Manganese (Mn) | 0.40–0.60 |
| Phosphorus (P) | 0.035 Max. |
| Sulfur (S) | 0.040 Max. |
| Silicon (Si) | 0.15–0.35 |
| Chromium (Cr) | 0.80–1.10 |
| Molybdenum (Mo) | 0.15–0.25 |
AISI 4130 – Mechanical Properties
| Property | Typical Value |
|---|---|
| Tensile Strength | 560–760 MPa |
| Yield Strength | 360–460 MPa |
| Elongation | 20–28% |
| Brinell Hardness | 156–217 HB |
| Modulus of Elasticity | Approx. 205 GPa |
AISI 4130 – Physical Properties
| Property | Typical Value |
|---|---|
| Density | 7.85 g/cm³ |
| Melting Range | Approx. 1,425–1,510°C |
| Thermal Conductivity | Approx. 42–46 W/m·K |
| Specific Heat Capacity | Approx. 477 J/kg·K |
| Coefficient of Thermal Expansion | Approx. 11.5–12.5 × 10⁻⁶/°C |
| Magnetic Properties | Magnetic |
AISI 4130 – Equivalent Grades
| Standard | Equivalent Grade |
|---|---|
| AISI / SAE | 4130 |
| UNS | G41300 |
| EN / DIN | 25CrMo4 |
| EN Material Number | 1.7218 |
| BS | 708A25 (commonly referenced) |
| JIS | SCM430 (approximate equivalent) |
| GB / China | 30CrMo (approximate equivalent) |
| ISO | 25CrMo4 (commonly referenced designation) |
Available Forms
Depending on manufacturer capability and project requirements, AISI 4130 may be available in several forms.
AISI 4130 Round Bars and Forged Bars
Used for shafts, axles, machined parts and mechanical components subjected to specified loads.
AISI 4130 Plates and Sheets
Used in the manufacture of specialized industrial components and engineered parts.
AISI 4130 Tubes
Used in selected mechanical, structural and oil and gas applications when the product meets the required tubing specification.
AISI 4130 Forgings
Used for components requiring specified mechanical properties and suitable material integrity.
Product availability, dimensional tolerances and delivery conditions should be confirmed for each enquiry.
Heat Treatment of AISI 4130
AISI 4130 can undergo heat treatment to achieve the properties required for a particular application.
Common processes include:
Annealing: Used to reduce hardness and improve suitability for certain machining and forming operations.
Normalizing: Helps establish a suitable microstructure and consistent properties.
Quenching: Increases hardness and strength when performed under suitable conditions.
Tempering: Adjusts the balance between strength, hardness and toughness after quenching.
Heat-treatment parameters must be selected according to the product dimensions, initial condition, required properties and applicable manufacturing specification.
Welding and Machining
AISI 4130 can be welded and machined, but the appropriate procedures depend on its composition, thickness and material condition.
Welding Considerations
Select compatible welding consumables.
Use qualified welding procedures where required.
Apply preheating when specified by the approved procedure.
Control cooling conditions.
Perform post-weld heat treatment when required.
Inspect the finished joint according to the applicable code.
Machining Considerations
Select cutting tools suitable for the material condition.
Adjust cutting speed and feed to the hardness and section size.
Manage heat generation during machining.
Verify dimensions and surface finish after processing.
Welding and machining parameters should be validated by the manufacturer or responsible engineering team.
Applications
Oil and Gas Industry
Mechanical components for oilfield equipment
Selected equipment parts and engineered components
Tubular applications where the required product specification permits the grade
Mechanical Engineering
Shafts and axles
Machined components
Load-bearing mechanical parts
Energy and Industrial Equipment
Specialised machinery components
Forged parts for industrial equipment
Components requiring controlled mechanical properties
Transportation and Engineering
Specialised mechanical structures
Engineered tubular components
Applications requiring an appropriate balance of strength, toughness and weight
Final material selection must account for design loads, operating conditions, safety requirements and the relevant industry standards.
AISI 4130 vs. AISI 4140 Alloy Steel
AISI 4130 and AISI 4140 are both chromium-molybdenum low-alloy steels, but they differ in composition and achievable properties.
AISI 4130: Nominally contains approximately 0.30% carbon and is often selected for a balance of strength, toughness and fabrication characteristics.
AISI 4140: Generally has a higher carbon content, which can allow higher strength and hardness after suitable heat treatment.
The appropriate grade depends on the required mechanical properties, product geometry, heat treatment, weldability and service conditions. Neither grade should automatically replace the other without technical evaluation.
Quality Control and Certification
Depending on the purchase order and applicable specification, quality assurance may include:
- Material test certificate
- Chemical composition analysis
- Mechanical testing
- Dimensional inspection
- Hardness testing, where required
- Visual examination
- Additional testing specified by the project
- Batch identification and material traceability
The inspection scope and documentation should be agreed with the manufacturer and stated in the purchase order.
Emirerri Steel – AISI 4130 Alloy Steel Supplier
Emirerri Steel supports industrial buyers seeking alloy steel products for oil and gas, energy, mechanical engineering and industrial manufacturing applications.
We can review enquiries for AISI 4130 round bars, plates, tubes and forgings according to required dimensions, material condition, applicable standards, quantities and inspection requirements.
Supply is subject to the agreed technical specification, manufacturer capability and availability.
Conclusion
AISI 4130 is a versatile chromium-molybdenum alloy steel used for mechanical and industrial components requiring suitable strength, toughness and heat-treatment characteristics. Correct selection depends on the product form, delivery condition, heat treatment and engineering requirements.
Contact Emirerri Steel to discuss your requirements for AISI 4130 alloy steel and other engineering-grade materials.
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