Alloy powder for oxidation-resistant coating, and alloy material formed of the powder and excellent in oxidation resistance characteristics

A method for producing an alloy material, comprising immersing an Ir-based alloy material or Ru-based alloy material that contains at least one of Al, Sc, Ti, V, Cr, Mn, Y, Zr, Nb, Mo, Tc, Hf, Ta, W or Re within a quantitative range within which any precipitation phase does not form, in a second mixed powder prepared by adding a metal chloride powder or an ammonia chloride powder to a mixed powder of a Ni—Al alloy and alumina, in an amount falling within a range of from 1% by mass to 6% by mass, at a temperature falling within a range of from 800° C. to 1300° C. for from 2 hours to 6 hours, thereby forming an IrAl intermetallic compound film or RuAl intermetallic compound film on a surface of the Ir-based alloy material or Ru-based alloy material,

• wherein the mixed powder of a Ni—Al alloy and alumina is prepared at least by heating a first mixed powder, which is prepared by mixing a Ni—Al mixed powder as prepared by mixing an Al powder with Ni in such a manner that Al therein could fall within a range of from 25 atomic % to 60 atomic %, and an alumina powder in a range of from 40% by mass to 60% by mass, in vacuum or in an inert gas atmosphere at a temperature falling within a range of from 600° C. to 1300° C. for at least 1 hour, and then grinding a resulting product.