AISI 8627 Steel Capillary

AISI 8627 Steel Capillary Product Information -:- For detailed product information, please contact sales. -: AISI 8627 Steel Capillary Synonyms -:- For detailed product information, please contact sales. -:

AISI 8627 Steel Product Information -:- For detailed product information, please contact sales. -: ### **Product Introduction: AISI 8627 Steel** #### **1. Overview** AISI 8627 is a **medium-carbon nickel-chromium-molybdenum (Ni-Cr-Mo) alloy steel**, positioned within the American Iron and Steel Institute (AISI) 8600 series as a **high-performance case-hardening (carburizing) grade**. Distinguished by its **elevated carbon content** relative to 8620/8625 grades, this steel is engineered to deliver **exceptional core strength, superior hardenability, and robust load-bearing capacity** while maintaining the fracture toughness characteristic of nickel-alloyed steels. Following carburizing heat treatment, it develops an optimal **"hard case, tough core"** microstructure, making it specifically suitable for **heavy-duty, high-stress components** that demand maximum resistance to bending, torsion, and contact fatigue beneath a wear-resistant surface. #### **2. International Standards & Designations** AISI 8627 is recognized under multiple international standards with regional equivalent designations. | Region/System | Standard Designation | Title / Purpose | | :--- | :--- | :--- | | **USA (AISI/SAE)** | **AISI 8627, SAE J404** | Standard Chemical Composition | | **USA (ASTM)** | **ASTM A322** | Standard Specification for Steel Bars, Alloy, Standard Grades | | **USA (ASTM)** | **ASTM A534** | Carburizing Steels for Anti-Friction Bearings | | **UNS Number** | **G86270** | Unified Numbering System | | **Europe (EN)** | **1.6528 / 27NiCrMo2-2** | Equivalent Material Standard | | **Germany (DIN/W-Nr.)** | **27NiCrMo2 / 1.6528** | Equivalent Designation | | **Japan (JIS)** | **SNCM420** (Close Equivalent) | Similar Material Standard | | **International** | **ISO 683-11: 27NiCrMo2-2** | International Material Standard | #### **3. Chemical Composition** The alloy composition is optimized for maximum core performance, with carbon content being the primary differentiator within the 862X series. | Element | Content (% by Weight) | Metallurgical Role | | :--- | :--- | :--- | | **Carbon (C)** | **0.25 - 0.30** | **Defining characteristic:** Provides highest core strength and hardenability in the 862X series. Basis for high-strength martensitic core after quenching. | | **Manganese (Mn)** | 0.70 - 0.90 | Enhances hardenability and solid solution strengthening. | | **Phosphorus (P)** | ≤ 0.035 | Residual impurity; controlled for ductility. | | **Sulfur (S)** | ≤ 0.040 | Residual impurity; controlled for transverse properties. | | **Silicon (Si)** | 0.15 - 0.35 | Deoxidizer; ferrite strengthener. | | **Nickel (Ni)** | 0.40 - 0.70 | **Critical for toughness:** Maintains ductility and impact resistance despite high carbon content; lowers ductile-brittle transition temperature. | | **Chromium (Cr)** | 0.40 - 0.60 | Enhances hardenability depth; promotes wear-resistant carbide formation in case. | | **Molybdenum (Mo)** | 0.15 - 0.25 | Increases hardenability; suppresses temper embrittlement; improves high-temperature strength. | | **Iron (Fe)** | Balance | Base metal. | #### **4. Mechanical & Physical Properties** *Properties vary with condition and heat treatment. Typical ranges are provided below.* **As-Supplied (Annealed) Properties:** * **Hardness:** **167 - 217 HB** (Brinell) * **Tensile Strength:** **570 - 725 MPa** (83 - 105 ksi) * **Yield Strength:** **425 - 585 MPa** (62 - 85 ksi) * **Elongation:** **18% - 24%** * **Machinability:** **~55%** of B1112 steel (Requires appropriate tooling and parameters). **Properties After Case Hardening (Carburized & Hardened):** * **Surface Case Hardness:** **58 - 63 HRC** (Rockwell C) * **Effective Case Depth:** Typically 0.6 - 2.5 mm (0.025" - 0.100"). * **Core Hardness:** **42 - 55 HRC** (Highest in the 862X series). * **Core Tensile Strength:** **1300 - 1650 MPa** (189 - 239 ksi) * **Core Yield Strength:** **1100 - 1450 MPa** (160 - 210 ksi) * **Impact Toughness:** Good for strength level, maintained by nickel. **Physical Properties (Core):** * **Density:** **7.85 g/cm³** (0.284 lb/in³) * **Modulus of Elasticity:** **205 GPa** (29,700 ksi) * **Poisson's Ratio:** **0.29** * **Thermal Conductivity:** **~43 W/m·K** at 100°C * **Coefficient of Thermal Expansion:** **12.3 × 10⁻⁶/°C** (20-100°C) #### **5. Product Applications** AISI 8627 is selected for the most demanding applications requiring maximum core strength combined with excellent surface wear resistance. * **Extreme-Duty Gearing:** Largest gears for mining excavators, draglines, heavy industrial reducers, marine propulsion, and wind turbine main gearboxes. * **Ultra-High-Load Bearings:** Bearing races and rollers for extreme service in rolling mills, large crushers, and heavy machinery. * **Critical Automotive/Truck Components:** Final drive pinions, crown wheels, and transmission gears for ultra-heavy-duty trucks and off-highway equipment. * **Oil & Gas Drilling Equipment:** Critical components in top drives, rotary tables, and downhole tools subject to extreme shock loads. * **Power Generation Machinery:** High-torque gears and shafts in turbine drives and large compressor systems. * **Defense & Aerospace:** Heavily loaded landing gear components, tank transmission gears, and other high-stress armament parts. #### **6. Key Characteristics & Advantages** * **Maximum Core Strength in 862X Series:** The highest carbon content (0.25-0.30%) delivers superior core hardness and tensile strength, enabling support of extreme loads. * **Exceptional Hardenability:** Capable of through-hardening very large section sizes (potentially >150mm/6" diameter) while maintaining core properties. * **Maintained Toughness:** Nickel content ensures respectable impact resistance despite the high strength level, preventing brittle fracture. * **Outstanding Bending Fatigue Resistance:** The strong core provides unparalleled resistance to tooth bending fatigue in large gears. * **Superior Load Distribution:** Minimizes subsurface yielding under heavy contact loads, extending component life. * **Good Wear & Pitting Resistance:** Carburized case provides excellent surface durability. * **Weldability:** Requires careful procedure (preheat 200-300°C, low-hydrogen electrodes, post-weld tempering). **Process Considerations:** * **Higher Quenching Stress:** Increased carbon content raises risk of distortion/quench cracking; requires controlled quenching (e.g., hot oil, marquenching). * **Tempering Requirement:** Mandatory tempering (150-200°C) is critical to relieve stresses and optimize toughness. * **Machining:** Lower machinability than lower-carbon grades; requires robust tooling and possibly annealed condition for complex machining. **Conclusion:** **AISI 8627 represents the pinnacle of core strength within the standard 862X case-hardening steel series.** It is a specialized engineering material designed for applications where component size, load magnitude, or stress levels exceed the capabilities of 8620/8625 grades. While presenting greater processing challenges in terms of distortion control and machinability, its **unmatched combination of core strength, hardenability, and retained toughness** makes it the material of choice for the world's most demanding mechanical power transmission and load-bearing applications. For engineers designing gear systems, bearings, or shafts that operate at the outer limits of mechanical performance, AISI 8627 provides a proven, reliable material solution that balances ultimate strength with necessary fracture resistance. Its use is justified in applications where component failure carries extreme economic or safety consequences, and where maximum power density and service life are paramount design objectives. -:- For detailed product information, please contact sales. -: AISI 8627 Steel Specification Dimensions Size： Diameter 20-1000 mm Length <5745 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 8627 Steel Properties -:- For detailed product information, please contact sales. -:

Applications of AISI 8627 Steel Capillary -:- For detailed product information, please contact sales. -: Chemical Identifiers AISI 8627 Steel Capillary -:- For detailed product information, please contact sales. -:

Packing of AISI 8627 Steel Capillary -:- 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 Capillary 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 2216 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