Introduction
Incoloy 800H and Inconel 706 are both nickel-containing high-performance alloys used in demanding industrial environments, but they are designed for completely different engineering purposes. The key selection factor is not only alloy chemistry, but also component function, product form and service conditions.
Incoloy 800H (UNS N08810) is commonly selected for high-temperature static equipment such as furnace components, heat-processing equipment, heater parts and fabricated assemblies where thermal stability and corrosion resistance are required.
Inconel 706 (UNS N09706) is a precipitation-hardening nickel alloy commonly selected for rotating or high-stress components such as turbine and power-generation parts where mechanical strength after controlled heat treatment is critical.
For industrial buyers, choosing between Incoloy 800H and Inconel 706 requires understanding the difference between fabricated static structures and strength-critical rotating components.
Quick Answer: Incoloy 800H vs Inconel 706
- Choose Incoloy 800H:
when the application requires sheet or plate fabrication for high-temperature static equipment. - Choose Inconel 706:
when the component requires round bar, forging stock or machining for high-strength rotating parts. - 800H priority:
thermal stability, oxidation resistance and fabrication performance. - 706 priority:
mechanical strength, precipitation hardening and load-bearing capability.
Why These Two Alloys Serve Different Jobs
Although both alloys belong to the nickel alloy family, their engineering objectives are different.
| Selection Factor | Incoloy 800H | Inconel 706 |
|---|---|---|
| Main Design Purpose | High-temperature fabricated equipment | High-strength rotating or mechanical components |
| Typical Product Form | Sheet and plate | Round bar, forging stock |
| Manufacturing Route | Cutting, forming, welding and fabrication | Forging, machining and heat treatment |
| Main Performance Focus | Thermal stability and corrosion resistance | Strength and fatigue resistance |
What Is Incoloy 800H?
Incoloy 800H (UNS N08810) is an iron-nickel-chromium alloy developed for elevated-temperature applications. Its controlled carbon content and processing requirements provide improved high-temperature structural stability.
800H is frequently supplied as sheet and plate products according to ASTM B409 / ASME SB-409 and is commonly used for fabricated components exposed to high temperatures.
| Feature | Incoloy 800H |
|---|---|
| UNS | N08810 |
| Typical Product | Sheet and plate |
| Standard | ASTM B409 / ASME SB-409 |
| Applications | Furnace parts, heat exchangers, thermal processing equipment |
What Is Inconel 706?
Inconel 706 (UNS N09706) is a precipitation-hardening nickel-iron-chromium alloy designed for high-strength applications. Its performance depends strongly on the specified heat-treatment condition.
706 is commonly supplied as round bar or forging stock according to ASTM B637 / ASME SB-637 for components requiring high mechanical strength.
| Feature | Inconel 706 |
|---|---|
| UNS | N09706 |
| Typical Product | Round bar and forging stock |
| Standard | ASTM B637 / ASME SB-637 |
| Applications | Turbine components, power generation and high-load parts |
Incoloy 800H vs Inconel 706 Comparison Table
Although Incoloy 800H and Inconel 706 are both nickel-containing alloys, they are optimized for different component requirements. 800H focuses on high-temperature stability and fabrication performance, while 706 focuses on high mechanical strength after controlled heat treatment.
| Property | Incoloy 800H | Inconel 706 |
|---|---|---|
| UNS Number | N08810 | N09706 |
| Alloy Type | Iron-nickel-chromium alloy | Precipitation-hardening nickel-iron-chromium alloy |
| Main Product Form | Sheet and plate | Round bar and forging stock |
| Main Design Goal | High-temperature fabricated equipment | High-strength mechanical components |
| Strengthening Method | Controlled chemistry and processing | Precipitation hardening heat treatment |
| Typical Component Type | Static equipment and fabricated assemblies | Rotating and load-bearing components |
Chemical Composition Difference
The chemical composition of each alloy reflects its intended application. Incoloy 800H uses a controlled iron-nickel-chromium system for elevated-temperature stability, while Inconel 706 includes alloying elements that enable precipitation strengthening.
| Element | Incoloy 800H | Inconel 706 |
|---|---|---|
| Nickel | Provides corrosion resistance and high-temperature stability | Provides alloy stability and high-temperature performance |
| Chromium | Improves oxidation resistance | Improves oxidation and corrosion resistance |
| Strengthening Elements | Controlled carbon and alloy balance | Elements supporting precipitation hardening |
Static Equipment vs Rotating Components Selection Guide
The most important difference between these alloys is the type of component they are designed for. Buyers should first identify whether the part is a static structure or a rotating, high-load component.
| Component Requirement | Recommended Alloy | Reason |
|---|---|---|
| Furnace Components | Incoloy 800H | Excellent elevated-temperature stability |
| Heat Treatment Equipment | Incoloy 800H | Suitable for fabricated hot-section parts |
| Turbine Components | Inconel 706 | High strength after heat treatment |
| Forged Rotating Parts | Inconel 706 | Designed for mechanical loading |
Heat Treatment Difference
Heat treatment requirements are an important purchasing consideration, especially for precipitation-hardening alloys.
| Material | Heat Treatment Consideration |
|---|---|
| Incoloy 800H | Performance depends on product condition, chemistry and service exposure |
| Inconel 706 | Strength depends strongly on solution treatment and aging condition |
Material Standards and Product Specifications
For nickel alloy procurement, specifying the correct material standard is essential. The alloy name alone is not enough because different product forms require different specifications, testing requirements and delivery conditions.
| Material | Standard | Product Form |
|---|---|---|
| Incoloy 800H | ASTM B409 / ASME SB-409 | Plate, sheet and strip |
| Inconel 706 | ASTM B637 / ASME SB-637 | Bar, rod and forging stock |
Inspection and Documentation Checklist
For high-performance nickel alloys, purchasing teams should define inspection and documentation requirements before ordering. This helps ensure the supplied material matches the engineering requirements and production process.
| Requirement | Recommended Information |
|---|---|
| Material Identification | Alloy grade, UNS number, standard and heat number |
| Dimensions | Thickness, width, diameter, length and tolerance requirements |
| Heat Treatment Condition | Required delivery condition and applicable treatment requirements |
| Testing Requirements | Chemical analysis, mechanical testing, hardness, NDT or third-party inspection |
| Documentation | MTC, traceability records and inspection reports |
Recommended Incoloy 800H and Inconel 706 Products
The product form should match the manufacturing route. Flat rolled products are commonly selected for fabricated static equipment, while round bars are preferred for forged or machined mechanical components.
| Material | Recommended Product | Application |
|---|---|---|
| Incoloy 800H | ASTM B409 Incoloy 800H Sheet and Plate |
Furnace parts, heat exchangers and fabricated high-temperature equipment |
| Inconel 706 | ASTM B637 Inconel 706 Round Bar |
Forged and machined high-strength components |
Frequently Asked Questions
Can Inconel 706 replace Incoloy 800H?
No. These alloys are designed for different engineering purposes. Incoloy 800H is commonly used for high-temperature fabricated equipment, while Inconel 706 is designed for high-strength components requiring precipitation hardening.
Which alloy is better for high-temperature static equipment?
Incoloy 800H is commonly selected for static high-temperature equipment because it provides good thermal stability and fabrication performance.
Which alloy is better for rotating components?
Inconel 706 is typically considered for rotating and high-load components where high mechanical strength after heat treatment is required.
Why is product form important when buying nickel alloys?
Product form determines the manufacturing route. Sheet and plate are usually selected for fabrication, while round bar and forging stock are selected for machining and forged components.
Request Nickel Alloy Material Solution
Need Incoloy 800H sheet, plate or Inconel 706 round bar for high-temperature or high-strength applications?
Please provide alloy grade, product form, dimensions, quantity, standard and inspection requirements for technical evaluation and quotation.
Conclusion
Incoloy 800H and Inconel 706 are both advanced nickel alloys, but they solve different engineering problems. Incoloy 800H is mainly selected for static high-temperature fabricated equipment, while Inconel 706 is selected for rotating or mechanically loaded components requiring high strength.
Successful material selection requires consideration of alloy grade, product form, manufacturing route, heat treatment condition and inspection requirements.
By matching the alloy to the component function, engineers and purchasing teams can improve reliability, reduce material risk and achieve better long-term performance.
Post time: Aug-10-2026