Ovako 100CrMo7 824B Steel

Ovako 100CrMo7 824B Steel Product Information -:- For detailed product information, please contact sales. -: Ovako 100CrMo7 824B Steel Synonyms -:- For detailed product information, please contact sales. -:

Ovako 100CrMo7 824B Steel Product Information -:- For detailed product information, please contact sales. -: # **Ovako 100CrMo7 824B Steel** ## **Product Overview** Ovako 100CrMo7 824B is a **high-performance, molybdenum-alloyed bearing steel** engineered to deliver a superior combination of **hardenability, strength, and toughness**. This alloy is distinguished from standard 100Cr6 (52100) by the **strategic addition of molybdenum (Mo)**, which profoundly enhances its metallurgical characteristics. The **"824B"** designation represents Ovako's premium quality grade for this specific chemistry, characterized by **controlled processing and enhanced consistency**. This steel is designed for manufacturing critical components that require **deep and uniform through-hardening, high load-carrying capacity, and excellent resistance to rolling contact fatigue**, particularly in larger cross-sections or under demanding operating conditions. ## **Key Features & Benefits** * **Enhanced Hardenability and Through-Hardening:** The addition of molybdenum significantly increases the steel's hardenability. This ensures **uniform martensitic transformation in larger section sizes** compared to standard 100Cr6, preventing soft cores and guaranteeing consistent mechanical properties from surface to center in heavy components. * **Improved Strength and Toughness Balance:** Molybdenum acts as a potent strengthener and grain refiner. It contributes to higher **tensile and yield strength** at equivalent hardness levels and, importantly, improves the **toughness and fracture resistance** of the tempered martensite. This provides a wider safety margin against brittle fracture under shock or overload. * **Superior Rolling Contact Fatigue (RCF) Performance:** The combination of high, uniform hardness, a refined microstructure, and the inherent benefits of molybdenum leads to **excellent resistance to rolling contact fatigue**. This results in extended bearing life and higher reliability under high cyclic stresses. * **Better Temper Resistance and Dimensional Stability:** Molybdenum increases the steel's resistance to softening during tempering, allowing components to **retain hardness better at elevated operating temperatures**. It also contributes to more stable dimensions during heat treatment by reducing distortion tendencies. * **Controlled Quality for Predictable Performance:** The 824B grade ensures tight control over chemical composition and microstructure, resulting in **predictable heat treatment response and consistent mechanical properties** batch after batch, which is critical for high-reliability applications. ## **International Standards & Designations** This steel corresponds to a specific, Mo-alloyed bearing steel grade within European standards. | Region/Standard | Standard Designation | Common Name / Equivalent | | :--- | :--- | :--- | | **EUR (EN)** | **1.3536** | The direct standard designation. The name **100CrMo7** describes its chemistry (C~1%, Cr~1.5%, Mo~0.2%). | | **ISO** | **ISO 683-17: 100CrMo7** | Recognized variant within the bearing steel standard. | | **Germany (DIN / W-Nr.)** | **100CrMo7 / 1.3536** | | | **USA (AISI/ASTM)** | **No direct equivalent.** | Functionally similar to a modified **52100 with Molybdenum addition**, approaching characteristics of steels like **SAE 4118H** but with higher carbon. | | **Ovako Designation** | **824B** | **"824"** correlates with the material number 1.3536; **"B"** denotes a specific, controlled quality level within Ovako's production. | ## **Chemical Composition (Typical - %)** The composition is defined by the deliberate addition of molybdenum. | 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)** | **0.15 - 0.25** | **Key alloying element.** Dramatically increases hardenability; refines grain structure; improves toughness and strength; 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 (After Hardening & Tempering)** *Properties are for material heat-treated to optimal conditions (e.g., austenitized at 840-860°C, oil quenched, and tempered at 150-200°C).* * **Hardness (Hardened & Tempered):** **60 - 64 HRC** (Typical aim: 61-62 HRC for bearings) * **Ultimate Tensile Strength (UTS):** **2100 - 2400 MPa** * **Yield Strength (0.2% offset):** **1700 - 2000 MPa** * **Elongation at Break:** ~2-5% * **Reduction of Area:** ~15-30% * **Impact Toughness (Charpy V-notch):** **Superior to standard 100Cr6** at equivalent hardness, due to the molybdenum addition. * **Through-Hardening Capacity:** Excellent. Can achieve uniform hardness in sections **> 75 mm** diameter. * **Rolling Contact Fatigue Life (L10):** **Very Good to Excellent.** The refined, tough microstructure provides long life under high stress. ## **Typical Applications** This material is specified for high-performance, larger-sized components where standard 100Cr6 may not provide sufficient hardenability or toughness. * **Large-Diameter and Heavy-Section Bearings:** Slewing rings, large roller bearing rings, and bearings for wind turbine gearboxes, heavy machinery, and large electric motors. * **High-Load Gearing Components:** Gears and pinions in industrial gearboxes, especially those with large module teeth requiring deep hardenability. * **Critical Automotive and Truck Components:** High-performance wheel bearings, transmission bearings, and differential components for heavy-duty applications. * **Machine Tool and Industrial Spindles:** Spindles requiring high stiffness, wear resistance, and reliability in larger diameters. * **Aerospace and Defense Components:** Critical bearings and rotating parts where enhanced toughness and reliability are required. ## **Processing Guidelines (General)** * **Machining:** Best performed in a **soft-annealed or spheroidize annealed condition** (~200 HB). * **Heat Treatment:** 1. **Preheating:** Recommended to ~650-700°C. 2. **Austenitizing:** ~840-860°C in a protective atmosphere. 3. **Quenching:** Oil quenching. The high Mo content provides excellent hardenability, allowing full hardening with relatively mild quenchants. 4. **Tempering:** **Double tempering** in the range of 160-220°C is recommended to achieve optimal toughness and dimensional stability. The molybdenum provides strong secondary hardening resistance. * **Grinding:** Performed after hardening to achieve final dimensions. The refined structure offers good grindability. ## **Summary** **Ovako 100CrMo7 824B Steel** is a **strategically enhanced bearing steel** that addresses the limitations of standard 100Cr6 in larger sections and more demanding applications. The deliberate alloying with molybdenum transforms its performance profile, offering **deeper hardenability, higher strength, and notably better toughness**. For engineers designing larger, heavily loaded components or seeking to push the performance and reliability limits of bearing systems, the 824B grade provides a proven, high-integrity material solution. It represents an intelligent upgrade path where the operational demands exceed the capabilities of conventional bearing steel, ensuring longevity and reliability under severe service conditions. -:- For detailed product information, please contact sales. -: Ovako 100CrMo7 824B Steel Specification Dimensions Size： Diameter 20-1000 mm Length <5295 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 824B Steel Properties -:- For detailed product information, please contact sales. -:

Applications of Ovako 100CrMo7 824B Steel -:- For detailed product information, please contact sales. -: Chemical Identifiers Ovako 100CrMo7 824B Steel -:- For detailed product information, please contact sales. -:

Packing of Ovako 100CrMo7 824B Steel -:- 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 1766 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