Alloy 800H/HT (Incoly 800HT)
Characteristics
ALLOY800 HT is an austenitic, high-strength, solid-solution Ni-Fe-Cr alloy with controlled levels of carbon, aluminum, titanium, silicon, and magnesium, along with an increased content of aluminum plus titanium. A special solution annealing treatment imparts the highest creep-rupture strength above 700 °C (1290 °F) due to the precipitation of titanium carbide (TiC). At temperatures below 700 °C (1290 °F), the formation of gamma prime (γ´) precipitates leads to a reduction in ductility. The alloy exhibits excellent creep strength at temperatures above 700 °C (1290 °F), good resistance to reducing, oxidizing, and nitriding atmospheres, as well as to conditions that alternate between reducing and oxidizing environments. It also offers outstanding metallurgical stability during long-term exposure to high temperatures. However, for applications where frequent excursions to temperatures below 700 °C (1290 °F) cannot be excluded, or where parts of the material remain permanently below this threshold, the use of ALLOY800H is recommended.
Stock Form and Sizes
※ ◆1000㎜ ◎2000㎜ ▲3000㎜ ■3500㎜ ●4000㎜ ★2500㎜～3990㎜
Round Bars
Specification: ASTM B408/B564※ ASME SB408/SB564※ ※B564/SB564 Apply to Forged Bar Only
Stock Specification：800H/HT Dual
| size １〜13 | ||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1.2 | 1.6 | 2 | 2.6 | 3 | 3.5 | 4 | 4.4 | 5 | 5.3 | 6 | 7.1 | 8 | 8.95 | 10 | 12 | 12.7 |
| ★ | ★ | ★ | ||||||||||||||
| size 16〜50 | ||||||||||||||||
| 16 | 18 | 19 | 20 | 22 | 24 | 25 | 28 | 30 | 32 | 35 | 36 | 38 | 40 | 42 | 45 | 50 |
| ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ||||
| size 55〜135 | ||||||||||||||||
| 55 | 60 | 65 | 70 | 75 | 80 | 85 | 90 | 95 | 100 | 105 | 110 | 115 | 120 | 125 | 130 | 135 |
| ● | ● | ● | ● | ● | ● | ● | ● | ● | ★ | ★ | ★ | ★ | ||||
| size 140〜300 | ||||||||||||||||
| 140 | 145 | 150 | 160 | 165 | 170 | 180 | 190 | 200 | 210 | 220 | 230 | 250 | 280 | 300 | ||
| ★ | ★ | ★ | ★ | ★ | ★ | ★ | ||||||||||
Sourceable Ex-Stock Material for other Forms from Distributors World-Wide
| Equivalent | Round Bars | Plate | Pipe/Tube | Welding Rod & Wire | ||
|---|---|---|---|---|---|---|
| Min | Max | Min | Max | |||
| Incoly800HT | 12.7～203.2 | 0.51～50.8 | ○ | △ | ||
*○: Various sizes available in stock. △: Only limited sizes available in stock. ☆: Please contact us for more details.
* We can supply materials and products that comply with various standards including ASTM, ASME, AMS, and NACE standards. Please contact us for more details.
Corrosion resistance
The high nickel and chromium contents of Alloy800H/HT ensure excellent resistance to oxidation.
The alloys are also very resistant to carburization, nitridation and oxidizing sulphur-bearing atmospheres.
The protective oxide film which is formed is adherent in both static and cyclic conditions of heating and cooling, and resistance to carburization is enhanced when a thin film of oxide is formed on the alloy through pre-oxidation prior to service.
Resistance to hydrogen is excellent and Alloy800H/HT are standard materials used in the production of hydrogen in steam/hydrocarbon reforming processes.
Applications
Due to high strength during long periods of service and resistance to carburization and nitridation, ALLOY800H/HT have found many applications in steam/hydrocarbon reforming for components such as: pigtails, headers/collectors/manifolds, transfer piping, catalyst tubes (in lowpressure processes) and quench-system piping.
Typical applications are:
- ethylene pyrolysis tubing in convection and radiant sections – resistance to carburization and good mechanical properties
- ethylene dichloride cracking tubes ? resistance to carburization and to dry hydrogen chloride and chlorine
- cracking tubes used in the production of acetic anhydride and ketene – high strength, resistance to both carburization and the formation of sigma phase
- components, e.g. heat exchangers, piping systems etc., in coal conversion plants
- steam generator tubing in helium cooled, high temperature reactor systems ? high strength, resistance to helium and to steam
Chemical composition
| Ni | Cr | Fe | C | Mn | Si | Cu | P | S | Al | Ti | Al+Ti | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| min | 30.0 | 19.0 | bal. | 0.06 | 0.5 | 0.2 | 0.30 | 0.30 | ||||
| max | 32.0 | 22.0 | 0.10 | 1.5 | 0.7 | 0.5 | 0.015 | 0.010 | 0.60 | 0.60 | 1.2 |
※The values in the table are for reference only and do not guarantee minimum or maximum values. For further information, please contact us.
Mechanical properties（Round Bar）
| Yield Strength(Mpa) | Tensile Strength(Mpa) | Elongation(%) | Hardness(HB) | |
|---|---|---|---|---|
| ASTM Min Value | 170 | 450 | 30 | |
| Typical Values at RT | 245 | 559 | 40 | 140 |
Above standard values and typical values of Round Bar.
Please contact us with any questions about reference or value of plate and pipe.
※Grade 1
※The values in the table are for reference only and do not guarantee minimum or maximum values. For further information, please contact us.
International Standard Comparison Chart
| Material | Round Bars | Plates/Sheets | Pipe/Tube | |||
|---|---|---|---|---|---|---|
| Seamless | Welded | |||||
| ASTM | UNS N08810 |
UNS N08811 |
B408 | B409 | B407 | B163 |
| ASME | SB408 | SB409 | SB407 | SB163 | ||
| JIS | NCF800H | NCF800HT | H4553 | G4901 | H4552 | |
| DIN | 1.4876 | 1.4959 | 17460 | 17460 | 17459 | |
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