AISI 4137 Steel Foil/Strip

AISI 4137 Steel Foil Product Information -:- For detailed product information, please contact sales. -: AISI 4137 Steel Foil Synonyms -:- For detailed product information, please contact sales. -:

AISI 4137 Steel Product Information -:- For detailed product information, please contact sales. -: # **AISI 4137 Steel: Comprehensive Product Overview** ## **1. Introduction** AISI 4137 is a medium-carbon, chromium-molybdenum (Cr-Mo) alloy steel characterized by its **high strength, excellent toughness, and superior hardenability**. As part of the 4100 series, it shares the core benefits of chromium-molybdenum steels but is distinguished by a higher carbon content compared to grades like 4130 or 4135. This elevated carbon level provides greater achievable hardness and strength after heat treatment, making it suitable for highly stressed, high-wear components. It is commonly supplied in the annealed or heat-treated condition and is renowned for its good balance of strength and fatigue resistance. ## **2. Chemical Composition** The chemical composition of AISI 4137 is the foundation of its enhanced strength and hardenability. The key alloying elements and their functions are detailed below: | Element | Composition Range (% by weight) | Primary Function | | :--- | :--- | :--- | | **Carbon (C)** | **0.35 - 0.40** | **The defining increase from 4135.** Provides the primary basis for high hardness and tensile strength after heat treatment. | | **Manganese (Mn)** | 0.70 - 0.90 | Increases hardenability (depth of hardening) and contributes to strength. | | **Phosphorus (P)** | ≤ 0.035 | Residual element (impurity), kept low to preserve ductility and toughness. | | **Sulfur (S)** | ≤ 0.040 | Residual element (impurity), kept low. May be slightly elevated in free-machining variants (e.g., 4137 Modified). | | **Silicon (Si)** | 0.15 - 0.35 | Acts as a deoxidizer during steelmaking and provides solid solution strengthening. | | **Chromium (Cr)** | 0.80 - 1.10 | Enhances hardenability, improves wear and corrosion resistance, and strengthens at elevated temperatures. | | **Molybdenum (Mo)** | 0.15 - 0.25 | Significantly improves hardenability, increases high-temperature strength, and reduces susceptibility to temper embrittlement. | *Note: This is the standard AISI/SAE specification. Exact composition may vary slightly under different international standards or producer-specific modifications.* ## **3. Physical & Mechanical Properties** The properties of AISI 4137 are highly dependent on its heat treatment condition. The following are typical values for the material in a quenched and tempered state. * **Physical Properties:** * **Density:** 7.85 g/cm³ (0.284 lb/in³) * **Melting Point:** ~1420°C (2590°F) * **Modulus of Elasticity (Young's):** 190 - 210 GPa (29,000 - 30,500 ksi) * **Poisson's Ratio:** 0.29 * **Thermal Conductivity:** ~42.7 W/m·K (at 100°C) * **Coefficient of Thermal Expansion:** 11.5 µm/m·°C (20-100°C) * **Typical Mechanical Properties (After Quenching & Tempering):** * **Tensile Strength:** 900 - 1150 MPa (130,000 - 167,000 psi) * **Yield Strength (0.2% Offset):** 750 - 950 MPa (109,000 - 138,000 psi) * **Elongation (in 50mm / 2in):** 16% - 20% * **Reduction of Area:** 50% - 60% * **Hardness (Brinell):** 285 - 341 HB (Approx. 30-36 HRC, varies with tempering temperature) * **Charpy V-Notch Impact Energy:** 30 - 55 J (22 - 41 ft-lb) at room temperature. ## **4. Product Applications** AISI 4137 is favored for applications requiring a superior combination of **core strength, wear resistance, and fatigue life** in medium to large cross-sections. * **Automotive & Heavy Trucking:** **Crankshafts, axle shafts, transmission gears, drive pinions, and high-strength fasteners.** Its higher strength makes it suitable for high-performance or heavy-duty components. * **Oil & Gas Industry:** **Heavy-weight drill collars, tool joints, mandrels, and sucker rods** where increased yield strength and wear resistance are critical in demanding downhole environments. * **Aerospace:** **High-stress landing gear components, engine mounts, and airframe fittings** that require a higher strength-to-weight ratio than 4130/4135 can provide. * **Off-Highway & Construction Equipment:** **Track pins, rollers, final drive shafts, and heavily loaded gears** in excavators, bulldozers, and mining machinery. * **Power Transmission & General Engineering:** **Large-diameter shafts, spindles, couplings, and die blocks** that must withstand high torsional and bending stresses. ## **5. International Standards & Equivalent Grades** AISI 4137 is recognized globally under various national and international standards. | Standard / Country | Designation | Note / Status | | :--- | :--- | :--- | | **AISI / SAE (USA)** | **4137** | The primary reference standard. | | **ASTM (USA)** | A29 / A322 (Grade 4137) | Standard specification for alloy steel bars. | | **UNS** | G41370 | Unified Numbering System. | | **DIN (Germany)** | 34CrMo4 / 1.7220 | *Note: The DIN 34CrMo4 (1.7220) covers a carbon range that includes both 4135 and 4137. Precise selection is based on required mechanical properties.* | | **EN (Europe)** | 1.7220 / 34CrMo4 | Similar to DIN, a broad equivalent. | | **JIS (Japan)** | SCM435 / SCM440 | SCM435 (0.33-0.38%C) is closer to 4135, while SCM440 (0.38-0.43%C) is a closer match for 4137's higher carbon content. | | **GB (China)** | 35CrMo / 42CrMo | 35CrMo is a general equivalent, while 42CrMo offers a closer carbon match for higher strength requirements. | ## **6. Heat Treatment** Proper heat treatment is essential to unlock the full potential of AISI 4137. * **Annealing:** Heat to ~845°C (1550°F) and furnace cool to soften for machining (~ 179 HB max). * **Normalizing:** Heat to ~870-900°C (1600-1650°F) and air cool to refine the grain structure. * **Hardening (Quenching):** * **Austenitizing Temperature:** 830-850°C (1525-1560°F). * **Quenching Medium:** **Oil quenching** is standard for most sections. Larger sections may require a more aggressive quench (e.g., fast oil or polymer). * **Tempering:** **Immediately after quenching.** Reheat to a temperature between **540°C - 650°C (1000°F - 1200°F)**. Higher tempering temperatures yield higher toughness and ductility with lower strength/hardness, and vice-versa. **Double tempering** is often used to ensure complete transformation and stress relief. ## **7. Machinability & Weldability** * **Machinability:** Rated at approximately **65%** of that for a 1% carbon steel (100 series) in the annealed condition. It is considered fair to good; using proper tooling and coolants is recommended. * **Weldability:** **Fair.** Preheating (150-260°C / 300-500°F) and post-weld stress relieving or full heat treatment are **strongly recommended** to prevent cracking and restore mechanical properties in the heat-affected zone (HAZ). The higher carbon content compared to 4130 makes it more susceptible to weld cracking. ## **8. Conclusion** AISI 4137 steel is a **high-performance alloy** designed for applications where the **enhanced strength and hardness** provided by its higher carbon content are essential. It offers an excellent balance of hardenability, strength, and toughness when properly heat-treated. While it requires careful attention during welding, its superior load-bearing capacity makes it a premier choice for critical, high-stress components in the automotive, energy, aerospace, and heavy machinery industries. When selecting 4137, the required final mechanical properties should guide the precise specification and heat treatment process. -:- For detailed product information, please contact sales. -: AISI 4137 Steel Specification Dimensions Size： Diameter 20-1000 mm Length <6203 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 4137 Steel Properties -:- For detailed product information, please contact sales. -:

Applications of AISI 4137 Steel Foil -:- For detailed product information, please contact sales. -: Chemical Identifiers AISI 4137 Steel Foil -:- For detailed product information, please contact sales. -:

Packing of AISI 4137 Steel Foil/Strip -:- 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 Foil/Strip 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 2674 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