AISI 4130 Steel, annealed

AISI 4130 Steel, annealed at 865°C (1585°F), furnace cooled 11°C (20°F)/hour to 680°C (1255°F) Product Information -:- For detailed product information, please contact sales. -: AISI 4130 Steel, annealed at 865°C (1585°F), furnace cooled 11°C (20°F)/hour to 680°C (1255°F) Synonyms -:- For detailed product information, please contact sales. -:

AISI 4130 Steel, annealed at 865°C (1585°F), furnace cooled 11°C (20°F)/hour to 680°C (1255°F) Product Information -:- For detailed product information, please contact sales. -: ### **Product Introduction: AISI 4130 Steel, Fully Annealed Condition** **AISI 4130** is a versatile and widely used chromium-molybdenum (Cr-Mo) low-alloy steel known for its excellent combination of strength, toughness, and weldability. When subjected to the specific annealing cycle of **heating to 865°C (1585°F) followed by a controlled furnace cooling at 11°C/hour (20°F/hour) to 680°C (1255°F)**, the material achieves its **softest and most ductile state**. This microstructure, consisting primarily of coarse pearlite and ferrite (approaching a spheroidized structure), is engineered to provide **minimum hardness, maximum machinability, and optimal cold-forming characteristics** prior to any final heat treatment (such as quenching and tempering) or extensive machining operations. #### **1. Chemical Composition** The composition is the foundation of AISI 4130's properties. This remains unchanged by the annealing process. | Element | Content Range (%) | Primary Function | | :--- | :--- | :--- | | **Carbon (C)** | 0.28 - 0.33 | Provides hardenability and core strength after final heat treatment. | | **Manganese (Mn)** | 0.40 - 0.60 | Increases hardenability and strength. | | **Phosphorus (P)** | ≤ 0.035 | Impurity (kept low for toughness). | | **Sulfur (S)** | ≤ 0.040 | Impurity. | | **Silicon (Si)** | 0.15 - 0.35 | Deoxidizer, increases strength. | | **Chromium (Cr)** | 0.80 - 1.10 | Enhances hardenability, wear resistance, and high-temperature strength. | | **Molybdenum (Mo)** | 0.15 - 0.25 | Improves hardenability, strength at high temperatures, and reduces temper embrittlement. | #### **2. Microstructure & Purpose of Specified Annealing** * **Process:** Austenisize at 865°C → **Very Slow Furnace Cool (11°C/hr)** to 680°C → Air cool to room temperature. * **Metallurgical Goal:** This extremely slow cooling rate through the critical temperature range allows carbon to diffuse fully, promoting the formation of a **soft, coarse microstructure**. It minimizes internal stresses and produces a structure that is ideal for machining and cold working. * **Resulting Microstructure:** **Coarse lamellar pearlite and ferrite**, often with significant carbide spheroidization. This is the **softest condition** achievable for AISI 4130. #### **3. Physical & Mechanical Properties (In This Annealed Condition)** ***Key Point:** The properties listed below are **only for the material in this specific soft-annealed condition**. They are not representative of the high-strength potential of 4130 after quenching and tempering.* * **Density:** 7.85 g/cm³ (0.284 lb/in³) * **Hardness (Typical):** **~ 140-160 HB** (Brinell) / **~ 75-85 HRB** (Rockwell B). This is significantly softer than the normalized (~ 190 HB) or quenched & tempered conditions. * **Tensile Strength:** **~ 550 - 650 MPa (80 - 95 ksi)** * **Yield Strength (0.2% Offset):** **~ 350 - 450 MPa (51 - 65 ksi)** * **Elongation (in 50mm):** **~ 25 - 30%** (Very high ductility) * **Reduction in Area:** **~ 55 - 65%** * **Machinability:** **Excellent** (for an alloy steel). Rated at approximately **70% of a 1% carbon steel standard**. The soft structure allows for high material removal rates, good surface finish, and extended tool life. * **Cold Workability:** **Excellent.** Suitable for severe bending, forming, and drawing operations without cracking. #### **4. Subsequent Processing & Final Application** Material in this condition is **rarely used as a final product state**. Its primary purposes are: 1. **Machining Stock:** To facilitate complex and heavy machining of components (e.g., aircraft fittings, complex gears) before final heat treatment. 2. **Cold Forming Stock:** For parts requiring significant deformation, such as deep-drawn tubes or formed brackets. 3. **Stress Relief & Structure Preparation:** To eliminate prior processing stresses and create a uniform microstructure ideal for consistent results in subsequent hardening operations. **Final Heat Treatment:** Components machined from this stock are almost always **re-austenitized, quenched, and tempered** to achieve their service properties. Typical final treatment yields tensile strengths from 700 MPa to over 1100 MPa, depending on tempering temperature. #### **5. Product Applications (As Annealed Stock)** This material serves as the starting point for high-performance components across industries: * **Aerospace:** Machined landing gear components, engine mounts, structural fittings. * **Oil & Gas:** Machined parts for downhole tools, valve bodies, and wellhead components. * **Automotive Racing:** Machined chassis components, suspension parts, and roll cages (prior to final heat treat or use in as-welded structures). * **General Engineering:** Critical machined parts that require extensive material removal before hardening. #### **6. International Standards & Equivalent Grades** The base material AISI 4130 is recognized globally. The annealing process would be a customer-specific requirement. | Standard | Designation | Note | | :--- | :--- | :--- | | **AISI / SAE (USA)** | 4130 | Primary designation | | **AMS (Aerospace)** | AMS-S-6758 (forgings), AMS 6350 (sheet/strip) | Often specifies annealing or normalized condition | | **UNS** | G41300 | | | **ASTM (USA)** | A29 (bar), A519 (seamless tube) | | | **DIN (Germany)** | **25CrMo4** (Very close equivalent, 1.7218) | | | **EN (European)** | **1.7218** | | | **JIS (Japan)** | SCM430 | Slightly different Cr range | | **GB (China)** | 30CrMo | | #### **7. Key Advantages of This Specific Annealed Condition** * **Optimal Machinability:** Provides the easiest machining condition for this alloy, reducing manufacturing time and cost for complex parts. * **Maximum Ductility:** Allows for severe cold forming operations. * **Uniform Microstructure:** Creates a consistent starting point for predictable final heat treatment results. * **Low Residual Stress:** Minimizes distortion during machining and provides a stable foundation for subsequent processing. **Disclaimer:** The mechanical properties listed are typical for this specific annealing cycle and can vary based on the exact chemical composition within the range, original grain size, and furnace characteristics. This condition is a processing state, not a service state. Final part design must be based on properties achieved after all manufacturing and heat treatment steps are complete. Always refer to certified material test reports for critical applications. -:- For detailed product information, please contact sales. -: AISI 4130 Steel, annealed at 865°C (1585°F), furnace cooled 11°C (20°F)/hour to 680°C (1255°F) Specification Dimensions Size： Diameter 20-1000 mm Length <6193 mm Size:We can customized as required Standard： Per your request or drawing We can customized as required Properties（Theoretical） Chemical Composition -:- For detailed product information, please contact sales. -: AISI 4130 Steel, annealed at 865°C (1585°F), furnace cooled 11°C (20°F)/hour to 680°C (1255°F) Properties -:- For detailed product information, please contact sales. -:

Applications of AISI 4130 Steel, annealed at 865°C (1585°F), furnace cooled 11°C (20°F)/hour to 680°C (1255°F) -:- For detailed product information, please contact sales. -: Chemical Identifiers AISI 4130 Steel, annealed at 865°C (1585°F), furnace cooled 11°C (20°F)/hour to 680°C (1255°F) -:- For detailed product information, please contact sales. -:

Packing of AISI 4130 Steel, annealed at 865°C (1585°F), furnace cooled 11°C (20°F)/hour to 680°C (1255°F) -:- For detailed product information, please contact sales. -: Standard Packing: -:- For detailed product information, please contact sales. -: Typical bulk packaging includes palletized plastic 5 gallon/25 kg. pails, fiber and steel drums to 1 ton super sacks in full container (FCL) or truck load (T/L) quantities. Research and sample quantities and hygroscopic, oxidizing or other air sensitive materials may be packaged under argon or vacuum. Solutions are packaged in polypropylene, plastic or glass jars up to palletized 2664 gallon liquid totes Special package is available on request. E FORUs’ is carefully handled to minimize damage during storage and transportation and to preserve the quality of our products in their original condition