Manufacturer: Nippon Yakin Kogyo Co., Ltd
Model : NAS800

NAS800 (UNS N08800)
Heat-Resistant Nickel Alloy

NAS800 (NCF800, UNS N08800) is a nickel-iron-chromium alloy that provides high strength and excellent resistance to oxidation and carburization at high temperatures. It also offers excellent corrosion resistance in many aqueous environments. Nippon Yakin provides this product in plate, sheet, and strip forms.

Chemical Composition	32Ni-20Cr-0.4Ti-0.3Al
Product shape	Coil	Sheet	Plate
Workability	Whether for hot working or cold working, NAS800 offers workability similar to austenitic stainless steels. Operators should maintain temperatures between 1200 and 1230°C for hot working, although they may perform light work at temperatures as low as 850°C To prevent cracks, we recommend avoiding the temperature range between 650 and 800°C. Although cold workability is similar to austenitic stainless steels, work hardening tends to be slightly lower.
Weldability	You can weld NAS800 using techniques such as TIG, MIG, and shielded metal arc welding, just as with standard austenitic stainless steels. Welders often use AWS ERNiCr-3/AWS ENiCrFe-2 welding rods.
Heat Treatment	NAS800 exhibits an austenitic structure similar to austenitic stainless steels, and appropriate heat treatment procedures and requirements are similar. Typical heat treatments are as follows: Annealing 980-1060°C; rapid cooling.
Properties at High Temperatures	Because of its high nickel and chromium content, NAS800 resists oxidation and carburization at high temperatures. NAS800 is superior to Type 310S and approaches NAS800 in resistance to oxidation. Engineers widely use NAS800 in applications requiring heat resistance due to its superior high-temperature strength, which is nearly equal to that of NAS800. It does not become brittle from sigma phase precipitation during use. While users generally apply NAS800 at temperatures below 600°C, they recommend NAS800H/800T for applications that require superior creep properties at higher temperatures.
Corrosion resistance	NAS800 offers superior corrosion resistance in oxidizing corrosive environments such as nitric acid or nitric acid sulfuric acid. Likewise, it performs well in sodium salt and other molten salt environments, with stress corrosion cracking resistance surpassing standard austenitic stainless steels.

High Temperature Strength

Workability

Whether for hot working or cold working, NAS800 offers workability similar to austenitic stainless steels. For hot working, temperatures should be between 1000 and 1230°C, although light work may be done at temperatures as low as 650°C. To prevent cracks, we recommend avoiding the temperature range between 650 and 800°C. Although cold workability is similar to austenitic stainless steels, work hardening tends to be slightly lower.

Weldability

As with standard austenitic stainless steels, NAS800 may be welded using techniques such as TIG, MIG, and shield metal arc welding. AWS ERNiCr-3/AWS ENiCrFe-2 welding rods are often used.

Heat Treatment

NAS800 exhibits an austenite structure similar to austenitic stainless steels, and appropriate heat treatment procedures and requirements are similar. Typical heat treatments are as follows:

• Annealing: 980-1060°C; rapid cooling.

Properties at High Temperatures

Because of its high nickel and chromium content, NAS800 resists oxidation and carburization at high temperatures. NAS800 is superior to Type 310S and approaches NAS600 in resistance to oxidation. Offering superior high-temperature strength nearly equal to NAS600, NAS800 is widely used in applications requiring heat resistance, as it does not become brittle due to sigma phase precipitation during use. While NAS800 is generally used at temperatures below 600°C, NAS800H/800T are recommended for applications requiring superior creep properties at higher temperatures.

Corrosion Resistance

NAS800 offers superior corrosion resistance in oxidizing corrosive environments such as nitric acid or nitric acid-sulfuric acid. Likewise, it performs well in sodium salt and other molten salt environments, with stress corrosion cracking resistance surpassing standard austenitic stainless steels.

Applications

• Sheathed heater
• Furnace parts
• Heat treatment fixtures
• Heat exchangers