AISI 1340H Steel, oil quenched

AISI 1340H Steel, oil quenched from 830°C (1525°F), 540°C (1000°F) temper Product Information -:- For detailed product information, please contact sales. -: AISI 1340H Steel, oil quenched from 830°C (1525°F), 540°C (1000°F) temper Synonyms -:- For detailed product information, please contact sales. -:

AISI 1340H Steel, oil quenched from 830°C (1525°F), 540°C (1000°F) temper Product Information -:- For detailed product information, please contact sales. -: # **Product Datasheet: AISI 1340H Steel, Quenched and Tempered** ## **Product Description** This material is AISI 1340H medium-carbon alloy steel supplied in the **quenched and tempered (Q&T)** condition. The specific heat treatment protocol—**oil quenching from 830°C (1525°F)** followed by **tempering at 540°C (1000°F)**—produces a tempered martensitic microstructure with an optimal balance of high strength, good toughness, and excellent fatigue resistance. This treatment achieves a **strength class typically designated as "1000 F temper"** in industry terminology, indicating the tempering temperature and corresponding mechanical properties. The 25 mm (1 inch) round bar form ensures consistent through-hardening and uniform properties throughout the cross-section. ## **Key Features** - **High Strength-to-Weight Ratio**: Superior mechanical properties compared to normalized or annealed conditions - **Controlled Hardenability**: The "H" designation ensures consistent depth of hardening in the specified section size - **Good Toughness and Ductility**: The 540°C temper provides optimal combination of strength and impact resistance - **Excellent Fatigue Properties**: Suitable for dynamically loaded components - **Dimensional Stability**: Properly tempered condition minimizes residual stresses and distortion --- ## **1. Chemical Composition** | Element | Composition Range (%) | Purpose | |---------|---------------------|---------| | **Carbon (C)** | 0.37 - 0.44 | Primary hardening element, provides strength and wear resistance | | **Manganese (Mn)** | 1.35 - 1.65 | Enhances hardenability, contributes to strength | | **Phosphorus (P)** | ≤ 0.035 | Residual element (minimized) | | **Sulfur (S)** | ≤ 0.040 | Residual element (minimized) | | **Silicon (Si)** | 0.15 - 0.35 | Deoxidizer, strengthens ferrite | | **Iron (Fe)** | Balance | Base metal | *Note: The "H" grade includes specific hardenability bands (typically HI-H4 per SAE J1268) ensuring consistent through-hardening in 25 mm sections.* --- ## **2. Mechanical & Physical Properties** ### **Mechanical Properties (Typical for 25 mm round)** | Property | Value | Metric Units | Imperial Units | |----------|-------|--------------|----------------| | **Hardness** | 269 - 302 HB | 269 - 302 HB | 269 - 302 HB | | **Tensile Strength** | 950 - 1100 MPa | 950 - 1100 MPa | 138 - 160 ksi | | **Yield Strength (0.2% offset)** | 850 - 1000 MPa | 850 - 1000 MPa | 123 - 145 ksi | | **Elongation (in 50 mm)** | 15 - 20% | 15 - 20% | 15 - 20% | | **Reduction of Area** | 40 - 55% | 40 - 55% | 40 - 55% | | **Impact Energy (Charpy V-notch, RT)** | 35 - 55 J | 35 - 55 J | 26 - 41 ft-lb | | **Modulus of Elasticity** | 200 - 205 GPa | 200 - 205 GPa | 29 - 29.7 ×10⁶ psi | ### **Physical Properties** | Property | Value | |----------|-------| | **Density** | 7.85 g/cm³ | | **Thermal Conductivity (20°C)** | 46.6 W/m·K | | **Coefficient of Thermal Expansion (20-100°C)** | 11.5 ×10⁻⁶/°C | | **Specific Heat Capacity** | 460 J/kg·K | --- ## **3. Microstructural Characteristics** - **Core Structure**: Fine tempered martensite (tempered at 540°C/1000°F) - **Prior Austenite Grain Size**: ASTM 6-8 (refined) - **Non-Metallic Inclusions**: Maximum Level 2.0 per ASTM E45 - **Decarburization**: Typically ≤ 0.25 mm (0.010 inch) per side for hot-rolled bar --- ## **4. Product Specification & International Standards** ### **Product Details** - **Form**: Hot-rolled round bar, 25 mm diameter (1.0 inch) - **Condition**: Oil quenched from 830°C (1525°F) and tempered at 540°C (1000°F) - **Straightness**: Standard commercial tolerance (typically 3 mm/m) ### **Applicable International Standards** | Standard | Specification | Application | |----------|---------------|-------------| | **AISI/SAE** | AISI 1340H, SAE J1268 | Chemical composition and hardenability | | **ASTM** | ASTM A304 | Steel bars subject to hardenability requirements | | **ASTM** | ASTM A29/A29M | General requirements for steel bars | | **ISO** | ISO 683-18 | Heat-treatable steels (similar grade: 34Cr4) | | **EN** | EN 10083-3 | 34Cr4 (1.7035) - similar grade | | **JIS** | JIS G4052 | SCr440H - equivalent grade | | **UNS** | G13400 | Unified numbering system | | **AMS** | AMS 6320 | Aerospace material specification (similar) | ### **Quality Certifications** - Mill Test Certificate 3.1 per EN 10204 - Hardenability certification per SAE J1268 - Ultrasonic testing available upon request (ASTM A388) --- ## **5. Typical Applications** ### **Automotive Industry** - **Transmission Components**: Gears, shafts, synchronizer hubs - **Drivetrain Parts**: Axle shafts, drive shafts, half-shafts - **Steering Components**: Steering arms, tie rods, pitman arms - **Engine Parts**: Crankshafts, camshafts (for moderate-duty applications) - **Fasteners**: High-strength bolts, studs, and cap screws (Grade 8.8-10.9 equivalent) ### **Industrial Machinery** - **Power Transmission**: Gear shafts, spindle shafts, coupling shafts - **Hydraulic Components**: Piston rods, cylinder rods, hydraulic shafts - **Material Handling**: Forklift mast components, conveyor shafts - **Agricultural Equipment**: Tractor PTO shafts, gearbox components, implement shafts - **Construction Machinery**: Excavator pinions, loader components ### **General Engineering** - **High-Strength Fasteners**: Bolts, nuts, washers for structural applications - **Tooling Components**: Jigs, fixtures, and machine tool parts requiring strength - **Marine Applications**: Shafting for small vessels, marine hardware - **Mining Equipment**: Wear-resistant pins, bushings, and small components --- ## **6. Processing Characteristics** ### **Machining** - **Machinability Rating**: 55-60% of B1112 steel - **Recommended Cutting Speeds**: 30-45 m/min (100-150 SFM) for turning - **Tool Material**: Carbide or coated carbide recommended - **Coolant**: Required for optimal tool life and surface finish ### **Welding** - **Weldability Rating**: Fair to Poor (requires precautions) - **Preheat Temperature**: 150-260°C (300-500°F) required - **Post-Weld Heat Treatment**: Mandatory - stress relieve at 595-650°C (1100-1200°F) - **Welding Processes**: SMAW, GTAW with low-hydrogen electrodes - **Filler Metal**: AWS E10018-D2 or equivalent ### **Further Heat Treatment** - **Stress Relieving**: 595-650°C (1100-1200°F), 1 hour per inch of thickness - **Surface Hardening**: Suitable for induction hardening (case depth 1.0-3.0 mm typical) - **Nitriding**: Can be nitrided for additional surface hardness (typically 650-800 HV) --- ## **7. Comparison with Alternative Conditions** | Property | Q&T (540°C temper) | Normalized | Annealed | |----------|-------------------|------------|----------| | **Hardness (HB)** | 269-302 | 201-255 | 183-217 | | **Tensile Strength (MPa)** | 950-1100 | 655-795 | 580-655 | | **Yield Strength (MPa)** | 850-1000 | 415-550 | 340-415 | | **Elongation (%)** | 15-20 | 18-25 | 22-28 | | **Primary Application** | High-strength components | General purpose | Machining pre-treatment | --- ## **8. Technical Notes** ### **Hardenability Data (Jominy Test - Typical)** - J1 (1/16" from quenched end): 55-60 HRC - J4 (4/16"): 45-50 HRC - J8 (8/16"): 35-40 HRC - J12 (12/16"): 30-35 HRC *Demonstrates adequate through-hardening for 25 mm diameter in oil* ### **Design Considerations** 1. **Section Size Sensitivity**: Properties are guaranteed for the specified 25 mm section 2. **Notch Sensitivity**: Moderate - proper fillet radii and surface finish recommended 3. **Fatigue Limit**: Approximately 450-500 MPa for polished specimens 4. **Temperature Limitations**: Recommended service temperature: -40°C to 400°C ### **Quality Assurance** - Standard testing includes hardness, tensile, and microstructural examination - Optional testing: impact testing, hardenability verification, non-destructive testing - Traceability: Heat number traceable to original melt --- **Disclaimer**: The values provided are typical for the specified heat treatment and section size. For critical applications, testing of material from the actual production lot is mandatory. Properties may vary with exact heat treatment parameters, section size, and manufacturing history. Consult with material engineers for application-specific validation. **Revision**: 1.0 | **Date**: October 2023 | **Classification**: Commercial -:- For detailed product information, please contact sales. -: AISI 1340H Steel, oil quenched from 830°C (1525°F), 540°C (1000°F) temper Specification Dimensions Size： Diameter 20-1000 mm Length <6170 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 1340H Steel, oil quenched from 830°C (1525°F), 540°C (1000°F) temper Properties -:- For detailed product information, please contact sales. -:

Applications of AISI 1340H Steel, oil quenched from 830°C (1525°F), 540°C (1000°F) temper -:- For detailed product information, please contact sales. -: Chemical Identifiers AISI 1340H Steel, oil quenched from 830°C (1525°F), 540°C (1000°F) temper -:- For detailed product information, please contact sales. -:

Packing of AISI 1340H Steel, oil quenched from 830°C (1525°F), 540°C (1000°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 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 2641 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