Materials · Incoloy
Incoloy 800H and 800HT fasteners
Incoloy 800H fasteners, studs and machined parts, and their 800HT counterparts, made to your drawing in Willenhall for high temperature structural service.
N08810
Also N08811, W.Nr 1.4958 and 1.4959
0.05 to 0.10% C
Controlled carbon for strength
ASTM 5
Grain size or coarser
1 to 500
Prototypes to batches of several hundred
About the alloy
Built for strength at high temperature
HAGUE FASTENERS makes Incoloy 800H fasteners and 800HT fasteners in the UK for furnaces, petrochemical plant and power generation. Incoloy 800H/800HT is an austenitic heat resistant alloy designed for high temperature structural applications.
Its strength comes from controlled levels of carbon, aluminium and titanium, together with a minimum anneal of 2100°F (about 1150°C) to achieve a grain size of ASTM 5 or coarser. That coarse grain gives better creep and rupture strength than standard Incoloy 800.
At a glance
- Austenitic heat resistant nickel-iron-chromium alloy
- Controlled carbon, aluminium and titanium
- 2100°F minimum anneal, grain size ASTM 5 or coarser
- For high temperature structural use
Composition
Incoloy 800H/800HT chemical composition
Percentage by weight.
| Element | Min % | Max % |
|---|---|---|
| Nickel (Ni) | 30.00 | 35.00 |
| Aluminium (Al) | 0.15 | 0.60 |
| Titanium (Ti) | 0.15 | 0.60 |
| Chromium (Cr) | 19.00 | 23.00 |
| Carbon (C) | .05 | 0.10 |
| Silicon (Si) | – | 1.00 |
| Copper (Cu) | – | 0.75 |
| Manganese (Mn) | – | 1.50 |
| Iron (Fe) | – | 39.50 |
| Sulphur (S) | – | 0.015 |
Properties
Mechanical properties (solution annealed, ASTM B408)
Specification minimums in the solution annealed condition, to ASTM B408.
| Property | Value |
|---|---|
| Tensile strength, min. | 450 MPa |
| Yield strength (0.2% offset), min. | 170 MPa |
| Elongation, min. | 30% |
This data is for general information only and may change without notice. HAGUE FASTENERS LIMITED believes it to be accurate but gives no warranty as to its accuracy or completeness and accepts no liability for its use. Actual properties may vary, and nothing here guarantees suitability for a particular use.
Equivalents and applications
Incoloy 800H/800HT equivalents and typical uses
Alternative designations
UNS N08811, UNS N08810, W.Nr 1.4958, W.Nr 1.4959, ASTM B409, ASTM B408, ASTM B407, ASME SB409, ASME SB408, ASME SB407, Code Case 1325.
Typical applications
- Furnace components and fixtures
- Petrochemical and refinery heaters
- Power generation plant
- High temperature pressure equipment
What we make
Fasteners we make in Incoloy 800H/800HT
Certification and testing
Certified, traceable and tested
Bar comes from approved UK, EU or US mills, with heat numbers carried through to release. Testing is by independent UKAS-accredited laboratories, with EN 10204 3.1 or 3.2 certificates as required. See quality and testing.
- Mill certificates and heat traceability
- PMI and chemical analysis
- Solution annealing by approved partners, with furnace charts
- Laser-marked heat codes or part numbers
Questions
Frequently asked questions
What is the equivalent of Incoloy 800H?
Incoloy 800H is UNS N08810 and W.Nr 1.4958. Incoloy 800HT is UNS N08811 and W.Nr 1.4959.
What is the difference between 800H and 800HT?
Both have controlled carbon and a coarse grain. 800HT adds tighter control of aluminium and titanium for higher strength at temperature.
Why use Incoloy 800H fasteners?
Incoloy 800H fasteners are used for structural parts at high temperature, where their creep and rupture strength outperform standard Incoloy 800.
Can you make 800HT studs to ASME SB408?
Yes. We make studs, bolts and nuts from bar to ASTM B408 or ASME SB408, or the specification you call up.
Incoloy 800H/800HT enquiry?
Send us your drawing or specification
Tell us the sizes, quantity and documentation you need, and we will reply quickly.