Alloy 800H,Incoloy 800H Other/Similar Specs,N08810,E FORU

British Specs:BS 3072 BS 3073 BS 3074 BS 3075 BS 3076 NA15，American Specs:AMS 5766 Bar and Forgings AMS 5871 Sheet, Strip and Plate ASTM B408 ASTM B564 ASTM A240 ASTM A480，German Specs:WS 1.4876 WS 1.4958 WS 1.4959

### **Technical Overview: Alloy 800H / Incoloy 800H & Related Specifications (UNS N08810)** --- #### **1.0 Comprehensive Product Overview** **Alloy 800H** (commercially known as **Incoloy 800H**, UNS **N08810**) represents a family of nickel-iron-chromium superalloys with controlled chemistry and processing to deliver optimal high-temperature performance. This overview covers the complete spectrum of Alloy 800H specifications, including closely related grades and their specific applications across various international standards. The "H" designation specifically indicates the high-temperature variant with controlled carbon content (0.05-0.10%) and aluminum/titanium ratios, providing enhanced creep rupture strength and microstructural stability compared to standard Alloy 800. --- #### **2.0 Chemical Composition Comparison** | Element | Alloy 800H (N08810) | Alloy 800 (N08800) | Alloy 800HT (N08811) | Role in the Alloy | |---------|---------------------|-------------------|---------------------|-------------------| | **Nickel (Ni)** | 30.0-35.0 | 30.0-35.0 | 30.0-35.0 | Austenitic structure, oxidation resistance | | **Chromium (Cr)** | 19.0-23.0 | 19.0-23.0 | 19.0-23.0 | High-temperature corrosion resistance | | **Iron (Fe)** | ≥39.5 | ≥39.5 | ≥39.5 | Balance element | | **Carbon (C)** | 0.05-0.10 | 0.05 max | 0.06-0.10 | **Key differentiator** - creep strength | | **Aluminum (Al)** | 0.15-0.60 | 0.15-0.60 | 0.25-0.60 | Oxidation resistance | | **Titanium (Ti)** | 0.15-0.60 | 0.15-0.60 | 0.25-0.60 | Stabilization and strengthening | | **Al + Ti** | ≥0.85 | - | ≥1.20 | **Critical for HT stability** | --- #### **3.0 Physical Properties Summary** | Property | Value | Condition/Notes | |----------|-------|-----------------| | **Density** | 8.03 g/cm³ (0.29 lb/in³) | Consistent across all 800 series | | **Melting Range** | 1354-1384°C (2470-2520°F) | - | | **Specific Heat** | 460 J/kg·K (0.11 Btu/lb·°F) | At 21°C (70°F) | | **Thermal Expansion** | 16.6 × 10⁻⁶ /K | 20-650°C range | | **Thermal Conductivity** | 15.6 W/m·K | At 21°C (70°F) | | **Electrical Resistivity** | 116 μΩ·cm | At 21°C (70°F) | | **Modulus of Elasticity** | 201 GPa (29.1 × 10⁶ psi) | At 21°C (70°F) | | **Magnetic Permeability** | <1.05 | Essentially non-magnetic | --- #### **4.0 Mechanical Properties Comparison** | Property | Alloy 800H (N08810) | Alloy 800 (N08800) | Alloy 800HT (N08811) | |----------|---------------------|-------------------|---------------------| | **Tensile Strength** | 450 MPa min | 515 MPa min | 450 MPa min | | **Yield Strength** | 170 MPa min | 205 MPa min | 170 MPa min | | **Elongation** | 30% min | 30% min | 30% min | | **Creep Strength** | **Excellent** | Good | **Superior** | | **Max Service Temp** | 815°C (1500°F) | 650°C (1200°F) | 815°C (1500°F) | --- #### **5.0 Comprehensive International Standards** **UNS Designations** - **N08810**: Alloy 800H (Standard high-temperature grade) - **N08800**: Alloy 800 (Standard grade) - **N08811**: Alloy 800HT (Enhanced high-temperature version) **ASTM/ASME Specifications** - **Plate, Sheet, Strip**: ASTM B409 / ASME SB-409 - **Rod, Bar**: ASTM B408 / ASME SB-408 - **Pipe, Tube**: ASTM B407, B163 / ASME SB-407, SB-163 - **Forgings**: ASTM B564 / ASME SB-564 - **Fittings**: ASTM B366 / ASME SB-366 **European Standards** - **EN 10095**: 1.4876 (X8NiCrAlTi32-21) - **DIN 17742**: 1.4876 / 2.4858 - **AFNOR**: Z8NC 33.21 **Other National Standards** - **JIS**: NCF 800H - **GB**: GH0800 (China) - **ISO 6207**: Nickel alloy specifications --- #### **6.0 Related Alloy Specifications** **Direct Variants** - **Alloy 800 (N08800)**: Standard version with lower carbon - **Alloy 800H (N08810)**: High-carbon version for creep resistance - **Alloy 800HT (N08811)**: Enhanced Al+Ti for maximum stability **Similar Performance Alloys** - **Alloy 801 (N08801)**: Enhanced carburization resistance - **Alloy 802 (N08802)**: Higher carbon for specific applications - **Alloy 825 (N08825)**: Enhanced corrosion resistance **International Equivalents** - **Incoloy 800H**: Special Metals Corporation - **NA 15**: British designation - **Nicrofer 3220**: ThyssenKrupp trade name --- #### **7.0 Application Spectrum by Specification** **N08810 (Alloy 800H) Applications** - Steam methane reformer tubes - Ethylene cracking furnace components - High-temperature heat exchangers - Industrial furnace radiant tubes **N08800 (Alloy 800) Applications** - General chemical processing equipment - Heat treating fixtures - Low-stress high-temperature components - Electrical heating elements **N08811 (Alloy 800HT) Applications** - Critical reformer outlet headers - Advanced cracking furnace systems - Nuclear heat exchangers - High-stress thermal processing equipment --- #### **8.0 Key Differentiating Factors** **Carbon Content Significance** - **N08800**: ≤0.05% C - General purpose - **N08810**: 0.05-0.10% C - Enhanced creep strength - **N08811**: 0.06-0.10% C - Maximum high-temperature performance **Aluminum + Titanium Control** - **N08810**: ≥0.85% Al+Ti - Standard high-temperature stability - **N08811**: ≥1.20% Al+Ti - Enhanced oxidation resistance and strength **Grain Size Requirements** - **All 800H variants**: Coarse grain structure for creep resistance - **Standard 800**: Fine grain structure for general applications --- #### **9.0 Selection Guidelines** **Choose Alloy 800 (N08800) for:** - Temperatures below 650°C (1200°F) - Moderate stress applications - General corrosion resistance requirements - Cost-sensitive projects **Choose Alloy 800H (N08810) for:** - Temperatures 650-815°C (1200-1500°F) - Creep and stress rupture critical applications - Long-term thermal stability requirements - Petrochemical furnace applications **Choose Alloy 800HT (N08811) for:** - Most demanding high-temperature applications - Maximum oxidation resistance requirements - Critical nuclear components - Extended design life requirements --- #### **10.0 Quality & Certification** **Standard Certifications** - PED 2014/68/EU Category - ASME Nuclear Certifications (N, NPT) - ISO 9001 Quality Management - ISO 14001 Environmental Management **Testing Requirements** - Chemical analysis per heat and product - Mechanical testing per heat treatment lot - Non-destructive examination as specified - High-temperature testing for critical applications **Documentation** - Mill Test Certificates 3.1 or 3.2 - Material test reports with full traceability - Compliance certificates to specified standards - Heat treatment charts and records --- ### **Technical Conclusion** The **Alloy 800 series (800/800H/800HT)** represents a carefully engineered family of nickel-iron-chromium alloys designed to meet specific high-temperature performance requirements. While sharing a common base composition, the controlled variations in carbon, aluminum, and titanium content create distinct performance characteristics that make each grade suitable for specific application environments. **Alloy 800H (N08810)** occupies the optimal position for most high-temperature applications, balancing excellent creep resistance, oxidation resistance, and cost-effectiveness. Understanding the subtle but critical differences between these related specifications enables engineers to select the most appropriate material for their specific service conditions, ensuring optimal performance, reliability, and cost efficiency throughout the component lifecycle.

Packing of Standard Packing: 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 1907 gallon liquid totes Special package is available on request.