Alloy 800H / 1.4876
Alloy 800H is an austenitic, heat resistant nickel-iron-chromium solid solution alloy with controlled levels of carbon, aluminum, titanium, silicon and manganese and controlled content of (Al + Ti)
Material Data Sheet
| Werkstoffnummer | 1.4876 / 1.4958 |
|---|---|
| Alloy | Alloy 800h |
| EN material name | X10NiCrAlTi32-20 |
| UNS | N 08810 |
| ASTM | ASME ASTM B409 |
| ASME SB409 | |
| ASTM A240 | |
| ASME SA240 | |
| ISO | FeNi32Cr21AlTi-HC |
| VdTÜV Data Sheet | 412, 434 |
Main fields of application of alloy 800H
Heat exchanger pipes at high temperatures quench systems High temperature areas in power plants Refineries ( E.g. flares) Laboratory Equipment Furnace construction
Chemical composition of alloy 800H
| C | Si | Mn | P | S | Cr |
|---|---|---|---|---|---|
| ≤ % | ≤ % | ≤ % | ≤ % | ≤ % | % |
| 0.01 | 0,1 | 0,50 | 0,025 | 0,015 | 22,0-24,0 |
| Ni | Al | Cu | Al+Ti | fe |
|---|---|---|---|---|
| % | % | ≤ % | ≤ % | ≤ % |
| 30.0-32.0 | 0.2-0.4 | 0,50 | max 0.7 | rest |
Comparison of the different Alloy 800 grades
| Alloy 800 | 800L | 800 | 800H | 800ht/hp |
|---|---|---|---|---|
| Werkstoffnummer | 1.4558 | 1.4876 | 1.4876/ 1.4958 | 1.4959 |
| UNS Number | N08880 | N08880 | N08810 | N08811 |
| Operating Temperature [C°]: | <550 | <600 | 600-950 | 700-1000 |
| Advantages | Corrosion resisting | Corrosion and heat resisting | Heat resisting, resistant to oxidation, carburization, nitration | Heat resisting, resistant to oxidation, carburization, nitration |
| Heat treatment | Soft annealed (920-980°C) | Soft annealed (920-980°C) | Solution annealed (1150°C) | Solution annealed(1150-1200°C) |
| Al+Ti content [%] | <=1,0 | <=1,0 | <=0,7 | 0,85-1,2 |
| C content | <0,025 | 0,04-0,08 | 0,06-0,10 | 0,06-0,10 |
| Ductility | very good | good | good | less good |
| VdTÜV | 412 | 412/434 | 412 | |
| DIN | 17459/17460 | |||
| SEW | 310/ 400 | 310/ 470 | 310 | 310 |
| Comment | Recommended for temperatures below 600°C | Stocked at Hempel, also useable for <700°C | Below 700 °C (1290 °F), gamma prime (γ´) precipitates combined with loss of ductility. |
Characteristics
Good creep resistance at temperatures above 600 ° C.
To avoid a weakening in strength between 500 and 700 ° C the content of Al + Ti is limited to max.0.7%
Good resistance to oxidizing, reducing and nitriding atmospheres and at varying oxidizing and carburizing conditions
Metallurgical stability in long-term use at high temperatures
Caution: If temperature 500-700 ° C is passed often during the process, 800h should be preferred. Alloy 800HT may show detrimental phases.
Hot forming
The material is hot formed within a temperature range of 900 and 1200 ° C and afterwards quenched rapidly in water or air. Hot bending is carried out at 1000 to 1150 ° C.
The annealing takes place at 1200 ° C.
Holding time about 60 min. / 100 mm thickness.
After hot forming, heat treatment for optimum creep strength is recommended.
Cold forming
The material has a higher work-hardening rate than austenitic stainless steels. The workpiece should be available in the annealed condition. For strong cold forming intermediate annealing is necessary.
For more than 10% deformation, annealing should be performed.
Heat treatment
The solution annealing is carried out at 1150 ° C. It should be cooled quickly under water.
With thicknesses less than about 1.5 mm rapid air cooling can be done.
Mechanical properties of 1.4876 / 1.4958
The following properties at room and elevated temperatures are in annealed condition and in accordance with the VdTÜV-Blatt. Varying values may be found in literature (e.g. VdTÜV sheet).
At RT Yield: 170N/mm²
Tensile: 450-700N/mm²
Creep rupture strength of 100.000h value (included VdTÜV safty value 1,5)
| 800h | 800ht/hp | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| According to | VdTÜV 412 | VdTÜV 412 | VdTüv 434 | VdTüv 434 | ASME UNS N08810 | ASME UNS N08810 | ASME UNS N08811 | ASME UNS N08811 | |
| (Al+ti)% | <=0,7 or 1,0 | <=0,7 or 1,0 | <=0,7 | <=0,7 | <=1,0 | <=1,0 | <=1,2 | <=1,2 | |
| t°C | T°F | N/mm² | ksi | N/mm² | ksi | N/mm² | ksi | N/mm² | ksi |
| 593 | 1100 | 11,5 | 11,5 | 80 | 11.5 | 89 | 13 | ||
| 600 | 1112 | 76 | 11 | 76 | 11 | 76 | 84 | ||
| 648 | 1200 | 7 | 7,5 | 7.5 | 8.5 | ||||
| 650 | 1202 | 49 | 7 | 51 | 7.5 | 50 | 56 | ||
| 700 | 1292 | 31 | 4.5 | 35 | 5 | 33 | 38 | ||
| 704 | 1300 | 4.5 | 5 | 32 | 5 | 37 | 5.5 | ||
| 750 | 1382 | 20 | 3 | 24 | 3.5 | 22 | 24 | ||
| 760 | 1400 | 2.5 | 3 | 3 | 3.5 | ||||
| 800 | 1472 | 13 | 1.8 | 16 | 2.2 | 15 | 17 | ||
| 815 | 1500 | 1.5 | 2 | 13 | 1.9 | 15.2 | 2.2 | ||
| 850 | 1562 | 7 | 1 | 10 | 1.6 | 10 | 11.7 | ||
| 871 | 1600 | 0.7 | 1.3 | 8 | 1.2 | 10 | 1.5 | ||
| 898 | 1650 | 0.4 | 1 | 7 | 1 | 7.5 | 1.1 | ||
| 900 | 1652 | 2,7 | 0.4 | 7 | 1 | 7 | 7.5 | ||
| 926 | 1700 | 0.8 | 5 | 0.7 | |||||
| 950 | 1742 | 5 | 0.7 | 4.5 | |||||
| 953 | 1750 | 0,6 | 4.5 | 0.6 | |||||
| 981 | 1800 | 0,5 | 3.5 | 0.5 | |||||
| 1000 | 1832 |
Filler metal (for welding with alloy 800H)
he following fillers are recommended:
FM 82
Werkstoff-Nr. 2.4806
SG/UP-NiCr20Nb
AWS A5.14 ERNiCr-3
Covered electrode
Werkstoff-Nr. 2.4648
EL-NiCr19Nb
AWS A5.11 ENiCrFe–3 mod.