AISI 4427 Steel Seamless tube

AISI 4427 Steel Seamless tube, heat treated in 25 mm rounds, reheated to 765°C (1410°F), 150°C (300°F) temper Product Information -:- For detailed product information, please contact sales. -: AISI 4427 Steel Seamless tube, heat treated in 25 mm rounds, reheated to 765°C (1410°F), 150°C (300°F) temper Synonyms -:- For detailed product information, please contact sales. -:

AISI 4427 Steel, heat treated in 25 mm rounds, reheated to 765°C (1410°F), 150°C (300°F) temper Product Information -:- For detailed product information, please contact sales. -: # **AISI 4427 Alloy Steel - Heat Treated Round Bars** ## **25mm Diameter, Quenched & Low-Temperature Tempered Condition** --- ### **1. PRODUCT OVERVIEW** **AISI 4427 Alloy Steel - Heat Treated Condition** - **Product Form:** 25mm (1 inch) diameter round bars - **Material Standard:** AISI 4427 / SAE 4427 - Medium Carbon Molybdenum Steel - **Applied Heat Treatment:** - **Austenitizing:** 765°C (1410°F) - Complete phase transformation - **Quenching:** Rapid cooling (typically oil quench) - **Tempering:** 150°C (300°F) - Low temperature stress relief - **Resulting Condition:** High hardness martensitic structure with moderate toughness - **Material Classification:** Medium-carbon, molybdenum-alloyed through-hardening steel - **Key Feature:** Good combination of strength and wear resistance at 25mm section size --- ### **2. CHEMICAL COMPOSITION** | Element | AISI 4427 Standard Range (%) | Typical Heat Analysis (%) | Metallurgical Function | |---------|-----------------------------|---------------------------|------------------------| | **Carbon (C)** | 0.24-0.29 | 0.26-0.28 | Primary strengthener, determines maximum hardness | | **Manganese (Mn)** | 0.60-0.80 | 0.65-0.75 | Enhances hardenability, solid solution strengthening | | **Phosphorus (P)** | ≤ 0.035 | ≤ 0.020 | Residual impurity (strictly controlled) | | **Sulfur (S)** | ≤ 0.040 | ≤ 0.025 | Residual impurity (can be modified for machinability) | | **Silicon (Si)** | 0.20-0.35 | 0.25-0.30 | Deoxidizer, strengthens ferrite, improves temper resistance | | **Molybdenum (Mo)** | 0.45-0.60 | 0.50-0.55 | **Key alloy:** Increases hardenability, reduces temper embrittlement | | **Nickel (Ni)** | - | ≤ 0.25 | Trace residual | | **Chromium (Cr)** | - | ≤ 0.20 | Trace residual | | **Copper (Cu)** | - | ≤ 0.35 | Trace residual | | **Iron (Fe)** | Balance | Balance | Matrix element | **Material Family Note:** AISI 4427 belongs to the "44xx" series where the first "4" indicates molybdenum as the primary alloying element (approximately 0.5%), and "27" indicates a nominal carbon content of 0.27%. --- ### **3. MATERIAL SPECIFICATIONS & STANDARDS** | Standard System | Designation | Equivalent/Related Standards | Notes | |----------------|-------------|-----------------------------|-------| | **UNS** | G44270 | Unified Numbering System | Primary identification | | **AISI/SAE** | 4427 | J404, J412 | Original designation | | **ASTM** | A322 | Grade 4427 alloy steel bars | Standard specification | | **ASTM** | A29/A29M | Hot-wrought and cold-finished steel bars | Quality requirements | | **AMS** | 6320 | Steel bars, forgings, and tubing (0.25-0.30C) | Aerospace material specification | | **ISO** | 683-11 | Heat-treatable steels, alloy steels | International standard | | **DIN** | 1.6510 | 26Mo5 | German equivalent (closest match) | | **JIS** | - | No direct equivalent | Similar to SCM420 with lower Cr | **Heat Treatment Standards Compliance:** - **Austenitizing:** Meets requirements of ASTM A255 (hardenability testing) - **Tempering:** Complies with ASTM A29 for tempering procedures - **Testing:** All testing per applicable ASTM standards --- ### **4. HEAT TREATMENT DETAILS** #### **Applied Thermal Processing:** 1. **Austenitizing Phase:** - **Temperature:** 765°C (1410°F) ±8°C - **Soak Time:** 60-75 minutes for 25mm diameter (ensures complete transformation) - **Atmosphere:** Neutral or protective to prevent decarburization and scaling - **Microstructural Goal:** Homogeneous austenite with complete carbon dissolution 2. **Quenching Process:** - **Medium:** Fast quenching oil (ISO VG 46 or equivalent) - **Agitation:** Moderate to high for uniform cooling - **Cooling Rate:** Sufficient to avoid pearlite/bainite formation in 25mm section - **Result:** Lath martensite with minimal retained austenite (<5%) 3. **Tempering Cycle:** - **Temperature:** 150°C (300°F) ±5°C - **Duration:** 90-120 minutes (follows rule of 1 hour per inch minimum) - **Cooling:** Still air to room temperature - **Purpose:** Stress relief, slight toughness improvement, ε-carbide precipitation #### **Microstructural Characteristics:** - **Matrix:** Tempered lath martensite - **Carbides:** Fine transition carbides (ε-carbide) distributed uniformly - **Prior Austenite Grain Size:** ASTM 7-8 (fine grain size) - **Retained Austenite:** Typically 3-6% - **Through-Hardening Capability:** Excellent for 25mm diameter with proper quench --- ### **5. MECHANICAL PROPERTIES (POST HEAT TREATMENT)** #### **Tensile Properties (Longitudinal Direction):** | Property | Typical Range | Testing Standard | Application Significance | |----------|---------------|------------------|--------------------------| | **Ultimate Tensile Strength** | 1600-1750 MPa (232-254 ksi) | ASTM E8/E8M | Very high strength capability | | **Yield Strength (0.2% offset)** | 1400-1550 MPa (203-225 ksi) | ASTM E8/E8M | Excellent resistance to permanent deformation | | **Elongation in 4D** | 9-13% | ASTM E8/E8M | Moderate ductility for high-strength material | | **Reduction of Area** | 35-48% | ASTM E8/E8M | Good energy absorption before fracture | | **Modulus of Elasticity** | 205 GPa (29.7×10⁶ psi) | - | Standard steel stiffness | #### **Hardness & Toughness Properties:** | Property | Typical Value | Testing Standard | Notes | |----------|---------------|------------------|-------| | **Surface Hardness** | 49-53 HRC | ASTM E18 | Consistent across circumference | | **Core Hardness (Center)** | 48-52 HRC | ASTM E18 | Excellent through-hardening | | **Charpy V-Notch Impact (20°C)** | 18-28 J (13-21 ft-lb) | ASTM E23 | Moderate impact resistance | | **Fatigue Limit (Rotating Bending)** | ~550-650 MPa | - | Good fatigue performance | | **Fracture Toughness (KIC)** | ~60-75 MPa√m | ASTM E399 | For reference only | #### **Hardness Distribution in 25mm Round:** | Radial Position | Hardness (HRC) | Microstructural Notes | |----------------|----------------|----------------------| | Surface (0mm) | 49-53 HRC | Fine tempered martensite | | 1/4 Radius (3.125mm) | 49-53 HRC | Uniform transformation | | Mid-Radius (6.25mm) | 49-52 HRC | Slight cooling rate effect | | Center (12.5mm) | 48-52 HRC | Complete martensite transformation | --- ### **6. PHYSICAL PROPERTIES** | Property | Value | Conditions / Notes | |----------|-------|-------------------| | **Density** | 7.85 g/cm³ (0.284 lb/in³) | At 20°C | | **Melting Range** | 1475-1510°C | Liquidus to solidus | | **Thermal Conductivity** | 43.0 W/m·K | At 100°C, heat-treated condition | | **Specific Heat Capacity** | 470 J/kg·K | At 20°C | | **Coefficient of Thermal Expansion** | 12.0 × 10⁻⁶/K | 20-200°C range | | **Electrical Resistivity** | 0.23 μΩ·m | At 20°C | | **Magnetic Properties** | Ferromagnetic | Below ~750°C Curie point | | **Poisson's Ratio** | 0.29 | Typical for steel | --- ### **7. TYPICAL APPLICATIONS** #### **High-Strength Fastening Components:** - **Grade 12.9 Bolts and Studs:** High-performance fasteners - **Heavy Equipment Fasteners:** Mining, construction machinery - **Pressure Vessel Studs:** High-tensile applications - **Structural Bolting:** Critical connections in steel structures #### **Wear-Resistant Machinery Parts:** - **Agricultural Components:** Plow bolts, cultivator shafts - **Construction Equipment:** Excavator bucket pins, linkage components - **Mining Tools:** Drill steel components, cutter bits - **Wear Plates and Liners:** Abrasion-resistant applications #### **Automotive and Transportation:** - **High-Stress Shafts:** Transmission shafts, axle components - **Suspension Components:** Heavy truck suspension pins - **Engine Components:** Camshafts, crankshafts (non-critical) - **Steering Linkage:** High-wear pivot points #### **Industrial Tooling and Components:** - **Jigs and Fixtures:** Precision locating pins, wear surfaces - **Machine Tool Parts:** Spindle components, tool holders - **Die Components:** Punches, ejector pins, guide posts - **Gauging Equipment:** High-wear measuring components #### **Special Applications:** - **Oil Field Tools:** Drill string subs, tool joints (non-corrosive environments) - **Hydraulic Components:** High-pressure piston rods, cylinders - **Material Handling:** Conveyor shafts, roller components --- ### **8. PROCESSING CHARACTERISTICS** #### **Machinability (Heat-Treated State):** - **Machinability Rating:** 35-40% (relative to 1212 steel as 100%) - **Recommended Tools:** Premium carbide grades (P20-P30), CBN for finishing - **Cutting Speeds:** 30-45 m/min for roughing, 60-90 m/min for finishing - **Feed Rates:** 0.15-0.25 mm/rev for roughing, 0.05-0.15 mm/rev for finishing - **Cooling Requirements:** Copious cutting fluid essential - **Chip Formation:** Short to medium breaking chips expected #### **Grindability:** - **Rating:** Good with proper wheel selection - **Recommended Wheels:** Aluminum oxide (A grade) or CBN wheels - **Important:** Avoid excessive heat generation to prevent tempering - **Cooling:** Always use grinding coolant #### **Forming and Straightening:** - **Cold Forming:** Not recommended in heat-treated state - **Straightening:** Possible with controlled hydraulic presses - **Risk:** High residual stresses and potential cracking #### **Welding Characteristics:** - **Weldability Rating:** Poor (Preheating and post-weld heat treatment mandatory) - **Preheat Temperature:** 200-300°C minimum - **Interpass Temperature:** 150-250°C - **Recommended Processes:** GTAW (TIG) with matching filler - **Post-Weld Treatment:** Immediate tempering at 300-400°C recommended - **Risk Factors:** High hardness leads to cracking susceptibility --- ### **9. ALTERNATIVE HEAT TREATMENT OPTIONS** | Tempering Temperature | Resulting Hardness (HRC) | Tensile Strength (MPa) | Charpy Impact (J) | Recommended Applications | |----------------------|--------------------------|------------------------|-------------------|--------------------------| | **150°C (300°F)** | 49-53 | 1600-1750 | 18-28 | **Current spec:** Maximum wear resistance | | **200°C (390°F)** | 46-50 | 1450-1600 | 25-35 | Improved toughness, good wear | | **315°C (600°F)** | 41-45 | 1250-1400 | 35-50 | Balance of strength and toughness | | **425°C (800°F)** | 36-40 | 1050-1200 | 45-60 | Enhanced impact resistance | | **540°C (1000°F)** | 31-35 | 900-1000 | 55-70 | Maximum toughness applications | --- ### **10. QUALITY ASSURANCE** #### **Standard Testing Protocol:** 1. **Chemical Analysis:** Optical emission spectrometry (ASTM E415) 2. **Hardness Testing:** Multiple locations including surface and center (ASTM E18) 3. **Microstructural Examination:** Grain size, martensite quality (ASTM E112) 4. **Surface Inspection:** Visual, magnetic particle or dye penetrant (ASTM E709/E165) 5. **Dimensional Verification:** Diameter, roundness, straightness per ASTM A29 #### **Certification Provided:** - Material Test Certificate 3.1 per EN 10204 - Full chemical analysis report - Heat treatment cycle documentation - Mechanical test results (hardness, typically) - Traceability to original heat number #### **Non-Conformance Criteria:** - Hardness outside specified range (48-53 HRC) - Excessive decarburization (>0.25mm depth) - Surface defects exceeding 0.5mm depth - Dimensional tolerance outside ±0.2mm for diameter --- ### **11. TECHNICAL COMPARISON** #### **Similar Grades Comparison:** | Grade | C% Range | Primary Alloy | 25mm Hardness after 150°C temper | Toughness (Charpy J) | Relative Cost | |-------|----------|---------------|----------------------------------|----------------------|---------------| | **AISI 4427** | 0.24-0.29 | Mo (0.5%) | 49-53 HRC | 18-28 | Medium | | **AISI 4422** | 0.20-0.25 | Mo (0.5%) | 48-52 HRC | 20-30 | Medium | | **AISI 4140** | 0.38-0.43 | Cr-Mo (0.9/0.2%) | 52-56 HRC | 15-25 | Medium | | **AISI 4340** | 0.38-0.43 | Ni-Cr-Mo | 52-56 HRC | 20-30 | High | | **AISI 1045** | 0.43-0.50 | Carbon only | 54-58 HRC | 10-20 | Low | #### **Unique Advantages of AISI 4427:** 1. **Carbon Optimization:** 0.27% carbon provides good hardenability without excessive brittleness 2. **Molybdenum Benefit:** Good through-hardening with reduced temper embrittlement risk 3. **Cost-Effective:** Lower alloy cost compared to Ni-Cr-Mo grades 4. **Consistent Response:** Predictable heat treatment behavior at 25mm section --- ### **12. DESIGN CONSIDERATIONS** #### **Recommended Applications:** - Components requiring high surface hardness - Applications with predominantly compressive loading - Situations where wear resistance is more critical than impact resistance - Precision components needing dimensional stability #### **Application Limitations:** - **Not recommended** for high-impact loading conditions - **Avoid** in corrosive environments without protection - **Not suitable** for dynamic fatigue loading with stress concentrations - **Exercise caution** with notched or threaded sections #### **Environmental Considerations:** - **Maximum Service Temperature:** 200°C continuous, 250°C intermittent - **Corrosion Resistance:** Similar to plain carbon steel (requires protective coating) - **Hydrogen Embrittlement:** Susceptible if electroplated (require baking) - **Stress Corrosion Cracking:** Increased risk at high hardness levels --- ### **13. PACKAGING AND HANDLING** #### **Standard Packaging:** - **Bundle Size:** 1-2 metric ton bundles - **Protection:** Rust preventive oil coating or VCI wrapping - **Identification:** Heat number, grade, size, hardness stamped or tagged - **End Marking:** Color-coded for quick identification (typically one white stripe) #### **Handling Precautions:** - **Hardness Hazard:** Material is extremely hard and can cause injury - **Brittleness:** May chip or crack if dropped or impacted - **Sharp Edges:** Machined surfaces are extremely sharp - **Storage:** Store in dry environment, protect from corrosion --- ### **14. TECHNICAL GUIDELINES FOR USE** #### **Machining Recommendations:** 1. **Always** use sharp cutting tools with positive rake angles 2. **Maintain** consistent feed rates to avoid work hardening 3. **Use** climb milling techniques where possible 4. **Consider** annealing prior to extensive machining if feasible #### **Joining Considerations:** 1. **Avoid welding** if possible; consider mechanical fastening instead 2. **If welding is necessary**, follow strict preheat and PWHT procedures 3. **Consider** silver brazing as an alternative joining method 4. **Threaded connections** should use fine threads to reduce stress concentration #### **Surface Treatment Options:** - **Phosphate coating:** Improves corrosion resistance and paint adhesion - **Black oxide:** Cosmetic and mild corrosion protection - **Electroplating:** With post-plate baking to prevent hydrogen embrittlement - **Nitriding:** Can further increase surface hardness (to 65+ HRC equivalent) --- **MATERIAL SELECTION SUMMARY:** AISI 4427 steel in this specific heat-treated condition offers an excellent balance of strength and moderate toughness for 25mm diameter components. The 765°C austenitizing temperature followed by 150°C tempering produces a predominantly tempered martensite structure with high hardness (49-53 HRC) and good wear resistance. This makes it particularly suitable for applications where resistance to abrasion and surface deformation is critical, while maintaining enough toughness to handle moderate shock loads. **APPLICATION RECOMMENDATION:** For components subjected to dynamic or impact loading, consider increasing the tempering temperature to 200-315°C to improve toughness at the expense of some hardness. Always conduct application-specific testing for critical components. --- **QUALITY ASSURANCE STATEMENT:** This material is produced and heat-treated under controlled conditions in compliance with ASTM A322 and A29 specifications. All material is traceable to original heat number with complete documentation available upon request. **DISCLAIMER:** The information provided represents typical values and characteristics. Actual properties may vary within acceptable specification ranges. For critical applications, testing of actual production material is strongly recommended. Consultation with a qualified materials engineer is advised for specific application requirements. -:- For detailed product information, please contact sales. -: AISI 4427 Steel, heat treated in 25 mm rounds, reheated to 765°C (1410°F), 150°C (300°F) temper Specification Dimensions Size： Diameter 20-1000 mm Length <4070 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 4427 Steel, heat treated in 25 mm rounds, reheated to 765°C (1410°F), 150°C (300°F) temper Properties -:- For detailed product information, please contact sales. -:

Applications of AISI 4427 Steel Seamless tube, heat treated in 25 mm rounds, reheated to 765°C (1410°F), 150°C (300°F) temper -:- For detailed product information, please contact sales. -: Chemical Identifiers AISI 4427 Steel Seamless tube, heat treated in 25 mm rounds, reheated to 765°C (1410°F), 150°C (300°F) temper -:- For detailed product information, please contact sales. -:

Packing of AISI 4427 Steel Seamless tube, heat treated in 25 mm rounds, reheated to 765°C (1410°F), 150°C (300°F) temper -:- 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 541 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