100CrMo7-3 825B Steel Wire

Ovako 100CrMo7-3 825B Steel Wire, Spheroidize annealing Product Information -:- For detailed product information, please contact sales. -: Ovako 100CrMo7-3 825B Steel Wire, Spheroidize annealing Synonyms -:- For detailed product information, please contact sales. -:

Ovako 100CrMo7-3 825B Steel, Spheroidize annealing Product Information -:- For detailed product information, please contact sales. -: # **Ovako 100CrMo7-3 825B Steel – Spheroidize Annealed Condition** ## **Product Overview** Ovako 100CrMo7-3 825B is a **specialized, high-carbon, high-molybdenum bearing steel** supplied in a **spheroidize annealed condition**, engineered for applications demanding **exceptional hardenability, high core strength, and superior toughness**. This alloy represents a distinct variant within the 100CrMo family, characterized by a **significantly elevated molybdenum content (approx. 0.3%)**. The **"825B"** designation indicates Ovako's **premium controlled-quality grade** for this specific chemistry, featuring enhanced homogeneity and consistent processing. The spheroidize annealed microstructure provides excellent machinability and prepares the material for achieving maximum hardness, deep hardenability, and outstanding mechanical properties after through-hardening heat treatment. ## **Key Features & Benefits** * **Exceptional Hardenability for Large Sections:** The high molybdenum content dramatically increases hardenability, enabling **full and uniform through-hardening in very large cross-sections** (significantly beyond standard 100Cr6 or even standard 100CrMo7). This prevents soft core formation and ensures consistent high hardness and strength throughout heavy components. * **Superior Strength and Toughness Combination:** Molybdenum is a potent strengthener and grain refiner. It contributes to **very high tensile and yield strength** at standard hardness levels while simultaneously **improving impact toughness and fracture resistance**. This provides an excellent balance for components subjected to both high static/dynamic loads and potential shock. * **Excellent Wear and Rolling Contact Fatigue Resistance:** The combination of high carbon, chromium, and molybdenum promotes a fine dispersion of hard, stable carbides within a tough martensitic matrix after hardening. This results in **outstanding resistance to abrasive wear and rolling contact fatigue**. * **Enhanced Temper and Thermal Stability:** The elevated molybdenum content significantly increases resistance to softening during tempering and exposure to moderate operational temperatures. This allows components to **retain hardness and strength better in warm environments** or permits the use of higher tempering temperatures to optimize toughness. * **Controlled Quality for Predictable Performance:** The 825B grade ensures tight control over chemical composition and a homogeneous spheroidized annealed structure. This leads to **predictable machining behavior, uniform response to heat treatment, and reliable final properties**, which is critical for high-value components. ## **International Standards & Designations** This steel corresponds to a specific high-molybdenum variant within bearing steel standards. | Region/Standard | Standard Designation | Common Name / Equivalent | | :--- | :--- | :--- | | **EUR (EN)** | **~1.3539** (Approximate) | The likely standard designation. The name **100CrMo7-3** describes its typical chemistry (C~1%, Cr~1.5%, Mo~0.3%). | | **ISO** | **ISO 683-17: 100CrMo7-3** | Recognized variant within the bearing steel standard. | | **Germany (DIN / W-Nr.)** | **100CrMo7-3 / ~1.3539** | | | **USA (AISI/ASTM)** | **No direct equivalent.** | Functionally similar to a high-hardenability modified **52100** with significant Mo addition, approaching some characteristics of **AISI 4340** but with higher carbon. | | **Ovako Designation** | **825B** | **"825"** correlates with the approximate material number; **"B"** denotes a specific, controlled quality level within Ovako's production. | ## **Chemical Composition (Typical - %)** The composition is defined by its elevated molybdenum content. | Element | Content (%) | Role | | :--- | :--- | :--- | | **Carbon (C)** | 0.93 - 1.05 | Provides the basis for high-carbon martensite and carbide formation. | | **Chromium (Cr)** | 1.40 - 1.70 | Enhances hardenability and promotes wear-resistant chromium carbides. | | **Molybdenum (Mo)** | **0.25 - 0.35** | **Key performance driver.** Dramatically increases hardenability and hardenability depth; refines grain structure; significantly improves toughness and strength; greatly enhances tempering resistance. | | **Manganese (Mn)** | 0.25 - 0.45 | Increases hardenability. | | **Silicon (Si)** | 0.15 - 0.35 | Deoxidizer and solid solution strengthener. | | **Sulfur (S)** | ≤ 0.010 | Kept low for good transverse properties. | | **Phosphorus (P)** | ≤ 0.020 | Kept low. | | **Iron (Fe)** | Balance | | ## **Physical & Mechanical Properties (Spheroidize Annealed Condition)** * **Delivery Hardness:** **190 - 220 HB** (Typical aim: ~205 HB) * **Microstructure:** **Fine spheroidized carbides** in a ferritic matrix. * **Tensile Strength:** ~700 - 850 MPa * **Yield Strength (Rp0.2):** ~450 - 600 MPa * **Elongation (A5):** ≥ 15% * **Machinability:** Good for its alloy content. ## **Properties After Hardening & Tempering (Typical Process)** * **Austenitizing:** 840-860°C. * **Quenching:** Oil quench. The high Mo content ensures full hardening even with moderate quench severity in large sections. * **Tempering:** 150-220°C. Double tempering is strongly recommended. Higher tempering temps (180-220°C) can be used to optimize toughness due to Mo's strong tempering resistance. * **Final Hardness:** **60 - 64 HRC** (Highly uniform through thick sections) * **Through-Hardening Capacity:** Can fully harden sections **> 100 mm** in diameter. * **Toughness:** Very good for the achieved hardness and strength level. ## **Typical Applications** This material is specified for large, heavily loaded components requiring guaranteed through-hardening and high performance. * **Large-Diameter, Heavy-Section Bearings:** Slewing rings for cranes and excavators, backup roll bearings, and large bearing rings for industrial gearboxes and wind turbines. * **Heavy-Duty Gearing for Large Machinery:** Main drive gears, pinions, and planetary gears in mining, marine, and heavy industrial equipment. * **High-Strength Shafts and Arbors:** Main spindles, kingpins, and axles for heavy machinery requiring deep hardenability and high torsional/bending strength. * **Tooling and Wear Parts for Severe Service:** Dies, forming tools, and wear plates where extreme compressive strength and wear resistance are needed in large cross-sections. * **Critical Components in Oil & Gas Equipment:** Large pins, links, and transmission parts in drilling and pumping equipment. ## **Processing Guidelines** * **Machining:** Perform all machining in the soft, spheroidize annealed condition. * **Heat Treatment (Customer Process):** 1. **Preheating:** Highly recommended to ~650-700°C. 2. **Austenitizing:** 840-860°C in a controlled atmosphere. Adequate soaking time is required. 3. **Quenching:** Agitated oil quench is standard. High hardenability allows for full hardening even with moderate quench rates, reducing distortion risk. 4. **Tempering:** **Double tempering** at 170-220°C is strongly recommended to achieve optimal toughness and dimensional stability. The high Mo content allows effective tempering at these temperatures without excessive hardness loss. * **Grinding:** Perform after hardening. Use proper techniques to avoid thermal damage. ## **Summary** **Ovako 100CrMo7-3 825B Steel in the Spheroidize Annealed condition** is a **high-performance engineering steel designed for the most demanding heavy-section applications**. Its elevated molybdenum content shifts its capabilities into a league beyond standard bearing steels, offering guaranteed deep hardenability, high strength, and remarkable toughness in large components. For engineers designing the core structural and rotating elements of mega-machinery—where material performance must be consistent from surface to center—the 825B grade provides a robust, reliable, and technologically advanced solution. It is the strategic choice when component size and load requirements exceed the capabilities of conventional through-hardening grades. -:- For detailed product information, please contact sales. -: Ovako 100CrMo7-3 825B Steel, Spheroidize annealing Specification Dimensions Size： Diameter 20-1000 mm Length <5300 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. -: Ovako 100CrMo7-3 825B Steel, Spheroidize annealing Properties -:- For detailed product information, please contact sales. -:

Applications of Ovako 100CrMo7-3 825B Steel Wire, Spheroidize annealing -:- For detailed product information, please contact sales. -: Chemical Identifiers Ovako 100CrMo7-3 825B Steel Wire, Spheroidize annealing -:- For detailed product information, please contact sales. -:

Packing of Ovako 100CrMo7-3 825B Steel Wire, Spheroidize annealing -:- 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 Wire 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 1771 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