Heat Resistant Alloys


  • JIS
  • UNSN08120
  • DIN/EN

NAS H38X (UNS N08120) is a high-nickel heat resistant alloy offering outstanding high-temperature strength and oxidation resistance. With coarse grain structure controlled by high temperature heat treatment and C, N, Nb components, NAS H38X offers particularly high creep strength. Nippon Yakin supplies NAS H38X in plate form.

Products & Materials

NAS H38XProductsPDF(201KB)

Chemical Composition 38Ni-25Cr-0.6Nb-0.2N
Product shape
Workability Cold workability is equivalent to standard austenitic stainless steel.
Weldability NAS H38X is weldable by TIG, MIG, and shielded arc welding processes. AWS A5.9 ER3556 welding electrodes are commonly used.
Heat Treatment NAS H38X exhibits an austenite structure similar to austenitic stainless steel and is heat-treated in the same way. Typical heat treatment is as follows.
・Solution treatment: 1,177~1,232℃, Rapid cooling
Pickling A mixture of nitric and fluoric acid is used in pickling.
Properties NAS H38X provides outstanding high-temperature strength, oxidation resistance, and carburization resistance, as well as excellent creep characteristics in temperatures of 800℃ and above.
Applications Heat treatment furnace parts, heat treating fixtures, and other high-temperature environments.