High temperature component and method for producing same
A method for producing a high temperature component includes a shaping step of shaping a powder compact of a desired high temperature component shape using a specific powder shaping method, from an alloy powder of γ′ precipitation strengthening-type Ni-based alloy, and a crystal grain coarsening step of coarsening a crystal grain size of the powder compact by heat treatment, wherein the powder compact contains 0.002% or more and 0.07% or less of C, and 5.40% or more and 8.40% or less of Al+Ti by mass percentage.
1. A method for producing a component, comprising:
a shaping step of injecting a compound obtained by kneading an alloy powder of γ′ precipitation strengthening Ni-based alloy and a resin binder into a mold to shape an intermediate compact, debindering the intermediate compact, and sintering the debindered intermediate compact to shape a powder compact of a desired component shape; and
a crystal grain coarsening step of coarsening a crystal grain size of the powder compact by heat treatment,
wherein the powder compact contains 0.002% or more and 0.07% or less of C, and 5.40% or more and 8.40% or less of Al+Ti by mass percentage.
2. The method according to claim 1 , further comprising:
a porosity reduction step of reducing a porosity by applying an isotropic pressure to the powder compact using a gas pressure, which is performed between the shaping step and the crystal grain coarsening step, or simultaneously with the crystal grain coarsening step.
3. The method according to claim 1 , wherein
the crystal grain coarsening step includes heating the powder compact at a predetermined coarsening temperature in a vacuum atmosphere or an inert gas atmosphere, and
the coarsening temperature is a temperature in the range of a pinning effect disappearance temperature specific to the powder compact or higher and a solidus temperature of the powder compact or lower.
4. The method according to claim 1 , wherein
the content of C in the powder compact is greater than 0.03% and 0.07% or less by mass percentage.
5. The method according to claim 1 , wherein the powder compact contains, in addition to C, Al, and Ti, 4.60% or less of Nb+Ta, 5.00% or more and 22.80% or less of Cr, 19.50% or less of Co, 1.80% or more and 13.75% or less of Mo+W, 0.10% or less of B, 1.0% or less of Zr, and 2.0% or less of Hf by mass percentage.
6. The method according to claim 1 , wherein
the powder compact contains 6.00% or more and 7.50% or less of Al+Ti, 1.50% or more and 3.00% or less of Nb+Ta, 11.00% or more and 15.00% or less of Cr, 3.80% or more and 5.20% or less of Mo, 0.005% or more and 0.020% or less of B, and 0.05% or more and 0.20% or less of Zr by mass percentage, with the balance being made up of Ni and inevitable impurities.
7. The method according to claim 1 , wherein
the average particle diameter of the alloy powder is 20 μm or more and 60 μm or less.
8. The method according to claim 1 , wherein
the alloy powder contains 0.002% or more and 0.02% or less of C by mass percentage.