2.4660
- N08020
- Alloy 20
Alloy 20 is an iron-base, austenitic alloy with excellent corrosion resistance to a number of different media and proves to be useful in a number of
applications such as flue-gas desulfurization, chemical processing, food processing and storage as well as pharmaceutical applications to name a few. Applications are limited to a maximum temperature of 537°C per ASME. This Alloy was developed for maximum resistance to acid attack, specifically sulfuric acid and fresh water tanks; crude petroleum stills, process vessels and piping; boiler feedwater heaters and heat exchangers; and deaerating heaters.
Mechanical Properties
| Tensile strength: | 550 | N/mm² |
| Yield strength 0,2% : | 240 | ≥ N/mm² |
| Elongation: | 30 | ≥ % |
| Hardness HB30: | 217 | ≤ HB |
Chemical Composition
Nickel
Ni
32-38% min
Carbon
C
0,07% max
Silicon
Si
1,00% max
Magnese
Mn
2,00% max
Sulphur
S
0,035% max
Copper
Cu
3-4% max
Molybdenum
Mo
2-3% max
Chromium
Cr
19-21% max
Heat Treatment
920-960°C followed by water quench.
Resistance to sulfuric acid is particularly exceptional but the alloy shows useful resistance in phosphoric acid, nitric acid as well as in chloride environments. Alloy 20 is an excellent option when chloride stress corrosion cracking is an issue and resists pitting and crevice corrosion.
can be welded by all the conventional methods. Proven welding processes are:
GTAW (TIG), GMAW (MIG), Plasma, PHW, SMAW.
Pulsed arc welding is the preferred technique.
Marking
All material will be marked as follow:
- Manufacturer’s name
- Material grade
- Size
- Heat Number
Certification
Material will be delivered with certificate EN 10204 3.1
