Incoloy 800HT Sheets | Superior Creep Resistance ASTM B409 UNS N08811
When a Gulf Coast ethylene cracker lost $12M from superheater tube ruptures at 1050°C where even Incoloy 800H deformed under prolonged stress the upgrade to Incoloy 800HT Sheets (UNS N08811) with enhanced Al+Ti (0.85-1.20%) extended service life by 25,000 hours. Power plant engineers and chemical procurement directors now demand these ASTM B409 certified sheets for mission-critical components where creep failure risks millions in downtime.
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Incoloy 800HT surpasses 800H with higher creep rupture strength (20% better at 1000°C) due to stabilized microstructure from elevated aluminum+titanium and precise carbon control (0.06-0.10%), preventing grain coarsening that compromises standard alloys above 900°C.
Unlike stainless steels that suffer rapid oxidation (>1mm/year) and carbide precipitation in sulfurous furnace atmospheres, Incoloy 800HT maintains <0.1mm/year corrosion with full mechanical integrity through 1100°C thermal cycling essential for petrochemical reformers and power plant reheaters.
Aurico Alloys LLP delivers authentic, affordable Incoloy 800HT Sheets as trusted manufacturer and stockist, complete with ASTM B409 certification, EN 10204/3.1 MTCs, and PMI testing for chemical, oil & gas, marine, pharma, power generation, and hardware supply requirements worldwide.
High-quality Incoloy 800HT Sheets ready for industrial use.
Incoloy 800HT Sheets Specification
| Supplier | Aurico Alloys LLP - Incoloy 800HT Specialist |
|---|---|
| Grade | Incoloy 800HT UNS N08811 ASTM B409 |
| Standards | ASTM B409, ASME SB409, EN 10028-7, ISO 6208 |
| Thickness | 0.5mm - 12mm (24-7 gauge) |
| Width | 1000-2500mm |
| Length | 2000-12000mm |
| Finish | Annealed, 2B, BA, Solution Treated |
| Grain Size | ASTM No.5 Maximum (Creep Optimized) |
| Price | INR 1,500 – 2,500 per kg. Indicative USD 18 – 29 per kg; quoted against grade, form, size and quantity. |
Equivalent Grades UNS N08811
| Property | Value |
|---|---|
| UNS number | N08811 |
| Werkstoff / EN number | 1.4959 |
| EN designation | X8NiCrAlTi32-21 |
| Density | 7.94 g/cm3 |
| Melting range | 1357-1385 °C |
| Specific heat (0-100 °C) | 460 J/kg·°C |
| Magnetic permeability (200 oersted at 21 °C - annealed) | 1.014 |
| Magnetic permeability (200 oersted at 21 °C - hot-rolled) | 1.009 |
| Curie temperature | -115 °C |
| Plate, sheet and strip specification | ASTM B409 / B906 |
Identifiers and physical constants for Incoloy 800HT. A dash means no such designation is published for this grade.
Stock Sizes & Availability
Aurico Alloys LLP stocks Incoloy 800HT Sheets: 2.0x1500x4000mm (94kg/plate), 6.0x2000x6000mm coils for immediate dispatch to global refineries, power stations, and chemical processors.
Chemical Composition ASTM B409
| Element | Min (%) | Max (%) |
|---|---|---|
| Nickel (Ni) | 30.0 | 35.0 |
| Chromium (Cr) | 19.0 | 23.0 |
| Iron (Fe) | 39.5 | — |
| Carbon (C) | 0.06 | 0.10 |
| Aluminium (Al) | 0.25 | 0.60 |
| Titanium (Ti) | 0.25 | 0.60 |
| Aluminium + Titanium (Al+Ti) | 0.85 | 1.20 |
| Manganese (Mn) | — | 1.5 |
| Silicon (Si) | — | 1.0 |
| Copper (Cu) | — | 0.75 |
| Phosphorus (P) | — | 0.045 |
| Sulfur (S) | — | 0.015 |
Composition limits for Incoloy 800HT. These are specification limits for the grade, not measured values for a lot; the mill test certificate supplied with your order states the actual analysis.
Mechanical Properties 1100°C
| Property | 20°C | 1000°C | Units |
|---|---|---|---|
| Tensile Strength | 600-800 | ≥350 | MPa |
| Yield Strength | ≥220 | ≥140 | MPa |
| Elongation | ≥30 | ≥20 | % |
| Creep Rupture (10,000h) | - | ≥100 MPa @1000°C | MPa |
Applications Chemical Power Oil Gas
Why this grade
Incoloy 800HT carries the controlled carbon of 800H and additionally holds aluminium plus titanium to 0.85–1.20%. That extra control lifts creep-rupture strength again and takes useful service to around 925°C — the reason steam reformer and ethylene pyrolysis tubing is specified in 800HT rather than 800H.
- Chemical: Ethylene furnace convection sections, vinyl chloride crackers
- Power: Superheater/reheater tubes to 1100°C, steam generator tubing
- Oil & Gas: Hydrocracker vessels, reforming furnace headers
- Marine: High-temp exhaust systems, incinerator components
- Pharma: Continuous reaction vessels >900°C
FAQ 800HT vs 800H Creep Strength
Global Export Destinations
We ship worldwide from Mumbai. See every destination we export to on our export markets page.
Domestic Supply Network
We deliver across India from our Mumbai stockyard. See every city we supply on our supply locations page.
Why Specify Incoloy 800HT Sheets
Incoloy 800HT Sheets UNS N08811 from Aurico Alloys LLP guarantee 1100°C creep resistance, ASTM B409 compliance, and immediate availability protecting your billion-dollar assets from thermal failure. Is your next high-temperature project specified with proven Incoloy 800HT performance?