Ovako 100CrMo7-3 825Q Steel

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

Ovako 100CrMo7-3 825Q Steel, Spheroidize annealing Product Information -:- For detailed product information, please contact sales. -: # **Ovako 100CrMo7-3 825Q Steel – Spheroidize Annealed Condition** ## **Product Overview** Ovako 100CrMo7-3 825Q is a **premium-grade, high-hardenability bearing steel** supplied in a **spheroidize annealed condition**, engineered for applications demanding **exceptional micro-cleanliness, deep hardenability, and superior fatigue performance**. This alloy represents Ovako's **qualified quality tier** within the high-molybdenum 100CrMo7-3 family, where the **"Q"** designation signifies **enhanced micro-cleanliness and controlled processing** compared to standard grades. The spheroidize annealed microstructure provides optimal machinability and a homogeneous foundation for achieving maximum hardness and outstanding mechanical properties—particularly in large cross-sections—after through-hardening heat treatment. ## **Key Features & Benefits** * **Enhanced Micro-Cleanliness for Superior Fatigue Life:** The 825Q grade features **reduced levels of non-metallic inclusions** (particularly sulfides and oxides) compared to standard industrial qualities. This improved internal cleanliness directly translates to **superior rolling contact fatigue (RCF) life and fracture toughness**, offering greater reliability and extended service life for critical, heavily loaded components. * **Exceptional Deep Hardenability:** The elevated molybdenum content (~0.3%) provides **outstanding hardenability**, enabling uniform through-hardening in **large section sizes (typically >100mm diameter)**. This prevents soft core formation and ensures consistent high hardness and strength throughout heavy components. * **Excellent Strength-Toughness Balance:** Molybdenum acts as a potent strengthener and grain refiner. It contributes to **high tensile and yield strength** at standard hardness levels while simultaneously **improving impact toughness and fracture resistance**. This provides an optimal balance for components subjected to high static/dynamic loads with potential shock exposure. * **Superior Machinability in Annealed State:** The spheroidize annealed condition produces a uniform hardness of **190-220 HB** and a fine dispersion of globular carbides, ensuring **good chip formation, extended tool life, and efficient machining** of complex part geometries prior to heat treatment. * **Controlled Quality for Predictable Performance:** As a defined "Q" grade, it offers guaranteed consistency in chemical composition, microstructure, and annealing response, providing a dependable and predictable material for high-reliability applications in demanding industries. ## **International Standards & Designations** This product is Ovako's premium quality variant of the high-molybdenum 100CrMo7-3 bearing steel. | Region/Standard | Standard Designation | Ovako Designation | Quality Level | | :--- | :--- | :--- | :--- | | **EUR (EN)** | **~1.3539 (100CrMo7-3)** | **100CrMo7-3 825Q** | **"Q" = Qualified, enhanced cleanliness grade.** | | **ISO** | **ISO 683-17: 100CrMo7-3** | | Meets and exceeds standard requirements for inclusion control. | | **Germany (DIN)** | **100CrMo7-3 / ~1.3539** | | Comparable to improved purity quality levels. | | **USA (AISI/ASTM)** | **No direct equivalent.** | | Considered a premium high-hardenability 52100 variant with significant Mo addition. | ## **Chemical Composition (Typical - %)** The composition adheres to strict 100CrMo7-3 limits with enhanced impurity control. | Element | Content (%) | Role & Quality Implication | | :--- | :--- | :--- | | **Carbon (C)** | 0.93 - 1.05 | Provides basis for high-carbon martensite. Uniform distribution is ensured. | | **Chromium (Cr)** | 1.40 - 1.70 | Enhances hardenability and promotes wear-resistant carbides. | | **Molybdenum (Mo)** | **0.25 - 0.35** | **Key alloying element.** Dramatically improves hardenability depth, toughness, and tempering resistance. | | **Manganese (Mn)** | 0.25 - 0.45 | Increases hardenability. | | **Silicon (Si)** | 0.15 - 0.35 | Deoxidizer and solid solution strengthener. | | **Sulfur (S)** | **≤ 0.008** | **Low sulfur** – a feature of the Q-grade. Minimizes MnS inclusions to enhance fatigue life and transverse properties. | | **Phosphorus (P)** | **≤ 0.015** | Kept low to maximize toughness. | | **Oxygen [O]** | **< 15 ppm** | Controlled low oxygen content to minimize oxide inclusions. | | **Iron (Fe)** | Balance | | ## **Physical & Mechanical Properties (Spheroidize Annealed Condition)** * **Delivery Condition:** **Spheroidize Annealed (+A)** * **Hardness:** **190 - 220 HB** (Typical aim: ~205 HB) * **Microstructure:** **Uniform dispersion of fine, spheroidized carbides** in a ferritic matrix. * **Tensile Strength:** ~700 - 850 MPa * **Yield Strength (Rp0.2):** ~450 - 600 MPa * **Elongation (A5):** ≥ 18% * **Machinability Rating:** **Excellent** for its alloy class. ## **Properties After Hardening & Tempering (Indicative)** * **Final Hardness:** **60 - 64 HRC** (via standard heat treatment: 840-860°C austenitize, oil quench, temper at 160-200°C) * **Ultimate Tensile Strength:** ~2100 - 2400 MPa * **Yield Strength:** ~1700 - 2000 MPa * **Impact Toughness:** **Very Good**, superior to standard 100Cr6 and comparable bearing steels, due to Mo addition and cleaner microstructure. * **Fatigue Performance:** **Excellent**, significantly benefiting from the cleaner microstructure. * **Through-Hardening Capacity:** Can fully harden sections **> 120 mm** in diameter. ## **Typical Applications** This annealed material is the preferred feedstock for high-performance, large-section components across demanding industries. * **High-Reliability Large-Diameter Bearings:** Slewing rings for cranes and excavators, large roller bearing rings for wind turbine gearboxes and heavy industrial gearboxes. * **Heavy-Duty Gearing Components:** Large module gears and pinions in mining, marine, and heavy industrial equipment requiring deep hardenability. * **Critical Automotive and Truck Components:** High-performance wheel bearings, transmission bearings, and differential components for heavy-duty applications. * **Machine Tool and Large Spindle Components:** Spindles and arbors requiring high stiffness, wear resistance, and reliability in larger diameters. * **Aerospace and Defense Components:** Critical bearings and rotating parts where enhanced toughness, fatigue life, and reliability are required. ## **Processing Guidelines** * **Machining:** All machining should be completed in the soft, spheroidize annealed state for optimal efficiency and tool life. * **Heat Treatment (Customer Process):** 1. **Preheating:** Recommended at 650-700°C, especially for large sections. 2. **Austenitizing:** 840-860°C in a protective atmosphere. Adequate soaking time is required for large masses. 3. **Quenching:** Oil quenching. The high Mo content ensures excellent hardenability even with moderate quench severity. 4. **Tempering:** **Double tempering** at 160-220°C is strongly recommended to achieve optimal toughness and dimensional stability. The molybdenum provides strong secondary hardening resistance. * **Grinding:** Perform final grinding after hardening. The consistent microstructure facilitates stable grinding operations. ## **Summary** **Ovako 100CrMo7-3 825Q Steel in the Spheroidize Annealed condition** is the **premium-quality feedstock for manufacturing high-performance, large-section through-hardened components**. It combines the profound deep-hardening capability of molybdenum alloying with the enhanced fatigue performance guaranteed by "Q" grade micro-cleanliness. This material provides a significant performance uplift over standard grades, offering **extended service life, greater reliability, and improved damage tolerance** in demanding applications. For engineers designing critical components where size, load, and longevity requirements push the limits of conventional bearing steels, the 825Q grade offers a proven, high-integrity solution that balances advanced metallurgical benefits with manufacturing efficiency. It represents the intelligent choice for engineering excellence in the most demanding mechanical systems. -:- For detailed product information, please contact sales. -: Ovako 100CrMo7-3 825Q Steel, Spheroidize annealing Specification Dimensions Size： Diameter 20-1000 mm Length <5306 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 825Q Steel, Spheroidize annealing Properties -:- For detailed product information, please contact sales. -:

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

Packing of Ovako 100CrMo7-3 825Q Steel, 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 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 1777 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