AISI 8622H Steel Seamless tube

AISI 8622H Steel Seamless tube, heat treated Product Information -:- For detailed product information, please contact sales. -: AISI 8622H Steel Seamless tube, heat treated Synonyms -:- For detailed product information, please contact sales. -:

AISI 8622H Steel, heat treated Product Information -:- For detailed product information, please contact sales. -: ### **Product Introduction: AISI 8622H Steel, Heat Treated** #### **1. Overview** AISI 8622H is a **hardenability-controlled (H-grade)** variant of the low-carbon nickel-chromium-molybdenum alloy steel, specifically engineered for applications requiring **guaranteed and consistent core properties** after heat treatment. The designation "heat treated" typically indicates the material has undergone **carburizing followed by quenching and tempering**, resulting in the classic **"hard case, tough core"** microstructure. With a carbon range slightly higher than AISI 8620H, this grade offers **enhanced core strength and hardenability**, making it particularly suitable for larger section sizes or components subjected to higher loads. The "H" designation ensures the steel's transformation characteristics fall within a narrow, specified band as verified by end-quench (Jominy) testing, providing **exceptional batch-to-batch consistency** in final mechanical properties. #### **2. International Standards & Designations** AISI 8622H conforms to international standards that govern both chemical composition and guaranteed hardenability. | Region/System | Standard Designation | Title / Purpose | | :--- | :--- | :--- | | **USA (AISI/SAE)** | **AISI 8622H, SAE J404 & SAE J1268** | Chemical Composition & Hardenability Bands | | **USA (ASTM)** | **ASTM A304** | Standard Specification for Carbon and Alloy Steel Bars Subject to End-Quench Hardenability Requirements | | **USA (ASTM)** | **ASTM A914/A914M** | Steel Bars Subject to Restricted Hardenability Bands | | **UNS Number** | **H86220** | Unified Numbering System for H-Steels | | **Europe (EN)** | **1.6565H / 22NiCrMo2-2H** | Hardenability-controlled Equivalent | | **Heat Treatment** | **SAE AMS-H-6875** | Heat Treatment of Steel, General Requirements | | **Case Hardening** | **AMS 2759/3** | Carburizing and Carbonitriding of Steel | #### **3. Chemical Composition & Hardenability Guarantee** The chemical composition is tightly controlled to ensure consistent hardenability within the specified "H-band," with carbon content being the key differentiator from 8620H. **Core Composition (% by Weight, AISI 8622H):** | Element | Content Range | Metallurgical Significance | | :--- | :--- | :--- | | **Carbon (C)** | **0.19 - 0.25** | **Primary differentiator:** Higher carbon provides increased core strength and hardenability compared to 8620H. | | **Manganese (Mn)** | 0.70 - 0.95 | Major hardenability agent; range adjusted to meet H-band specifications. | | **Phosphorus (P)** | ≤ 0.035 | Impurity control. | | **Sulfur (S)** | ≤ 0.040 | Impurity control. | | **Silicon (Si)** | 0.15 - 0.35 | Deoxidizer; solid solution strengthener. | | **Nickel (Ni)** | 0.35 - 0.75 | Enhances core toughness and hardenability. | | **Chromium (Cr)** | 0.35 - 0.65 | Increases hardenability; promotes wear-resistant carbides. | | **Molybdenum (Mo)** | 0.15 - 0.25 | Strong hardenability element; inhibits grain growth. | **Key Feature: Guaranteed Hardenability Band** The steel is certified to produce Jominy end-quench hardness values within a specified narrow range. This **guarantees predictable and uniform core hardness** after heat treatment, minimizing performance variation across production batches—a critical advantage for quality-critical applications. #### **4. Mechanical & Physical Properties (After Heat Treatment)** Final properties are achieved through carburizing, quenching, and tempering, with the H-grade ensuring superior consistency. **Properties After Case Hardening:** * **Surface (Case) Properties:** * **Hardness:** **58 - 63 HRC** (Rockwell C) * **Effective Case Depth:** Typically 0.5 - 2.5 mm, as specified. * **Wear Resistance:** Excellent against abrasion and pitting. * **Core Properties (H-Grade Advantage):** * **Hardness:** **38 - 48 HRC** (Typically 2-4 HRC higher than 8620H for equivalent sections due to higher carbon). * **Tensile Strength:** **1150 - 1450 MPa** (167 - 210 ksi) * **Yield Strength:** **950 - 1250 MPa** (138 - 181 ksi) * **Impact Toughness:** Good to very good, supported by nickel content. * **Section Size Capability:** Enhanced hardenability allows effective heat treatment of larger sections (up to ~125mm/5" diameter) while maintaining core properties. **Physical Properties (Core):** * **Density:** 7.85 g/cm³ * **Modulus of Elasticity:** 205 GPa * **Poisson's Ratio:** 0.29 * **Coefficient of Thermal Expansion:** 12.3 × 10⁻⁶/°C #### **5. Product Applications** Heat-treated AISI 8622H is specified for high-performance components where both surface durability and consistent core strength are critical, particularly in larger or more heavily loaded applications. * **Heavy-Duty Transmission Gearing:** Large gears for wind turbines, mining equipment, heavy truck transmissions, and industrial gearboxes. * **High-Load Bearing Components:** Races and rollers for large-diameter bearings in construction and agricultural machinery. * **Oil & Gas Equipment:** Heavy-duty downhole tools, large valve components, and pump gears. * **Aerospace Components:** Larger gears and shafts in auxiliary systems where material consistency is mandated. * **Power Transmission:** Large coupling components, heavy-duty splined shafts, and drive spindles. #### **6. Key Characteristics & Advantages** * **Guaranteed Core Consistency:** The **primary H-grade advantage**. Eliminates batch-to-batch variation in core hardness and strength, ensuring uniform performance and fatigue life. * **Higher Load Capacity:** The increased carbon content provides greater core strength than 8620H, allowing support of heavier loads beneath the hardened case. * **Superior Hardenability:** Enables successful heat treatment of larger section sizes while maintaining desired core properties. * **Reduced Manufacturing Risk:** Virtually eliminates scrap due to core hardness outliers, providing significant cost savings in high-value component production. * **Optimized for Quality-Critical Production:** The predictable transformation behavior allows for tighter process control and reduced inspection overhead. * **Excellent Fatigue Performance:** The combination of a hard, compressive-stressed case and a consistently strong core delivers reliable bending and contact fatigue resistance. **Conclusion:** **AISI 8622H in the heat-treated condition represents a premium engineering solution for demanding applications requiring guaranteed material consistency and enhanced load-bearing capacity.** It effectively bridges the gap between the excellent toughness of lower-carbon case-hardening steels and the higher strength of medium-carbon grades. The **H-grade certification transforms this material from a commodity into a reliability component**, providing manufacturers with the assurance that every production batch will deliver identical core properties after heat treatment. For applications involving larger sections, higher loads, or stringent quality requirements—particularly in heavy equipment, energy, and transportation sectors—AISI 8622H offers a technically advanced and economically sound choice that minimizes performance variability while maximizing component reliability. -:- For detailed product information, please contact sales. -: AISI 8622H Steel, heat treated Specification Dimensions Size： Diameter 20-1000 mm Length <5742 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 8622H Steel, heat treated Properties -:- For detailed product information, please contact sales. -:

Applications of AISI 8622H Steel Seamless tube, heat treated -:- For detailed product information, please contact sales. -: Chemical Identifiers AISI 8622H Steel Seamless tube, heat treated -:- For detailed product information, please contact sales. -:

Packing of AISI 8622H Steel Seamless tube, heat treated -:- 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 Seamless tube 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 2213 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