Turbine rotor blade and contact surface manufacturing method
A turbine rotor blade includes a blade body and a tip shroud on a tip of the blade body. The tip shroud has a contact block configured to face a tip shroud of an adjacent turbine rotor blade, and the contact block includes a base material, an oxidation resistant coating on the surface of the base material, and a hard wear resistant coating on the surface of the oxidation resistant coating.
1. A turbine rotor blade comprising:
a blade body; and
a tip shroud on a tip of the blade body,
wherein the tip shroud has a contact block configured to face a tip shroud of an adjacent turbine rotor blade, and
wherein the contact block includes:
a base material;
an oxidation resistant coating made of a MCrAlY alloy on a surface of the base material; and
a hard wear resistant coating on a surface of the oxidation resistant coating.
2. The turbine rotor blade according to claim 1 , wherein the MCrAlY alloy is a CoNiCrAlY alloy.
3. The turbine rotor blade according to claim 1 , wherein:
the hard wear resistant coating has a thickness of 0.02 mm or more and 0.30 mm or less; and
the oxidation resistant coating has a thickness of 0.02 mm or more and 0.20 mm or less.
4. The turbine rotor blade according to claim 1 , wherein a thickness of the oxidation resistant coating divided by a thickness of the hard wear resistant coating is 0.7 or more and 1.3 or less.
5. The turbine rotor blade according to claim 1 , wherein the oxidation resistant coating is at least on an area of a surface of the contact block that is configured not to be brought into contact with a contact block of the adjacent turbine rotor blade.
6. The turbine rotor blade according to claim 1 , wherein the hard wear resistant coating is only on the contact block.
7. The turbine rotor blade according to claim 1 , wherein the blade body has a thermal barrier coating on a blade surface of the turbine rotor blade.
8. A contact surface manufacturing method for forming a contact surface on a contact block of a tip shroud for a turbine rotor blade, the contact surface manufacturing method comprising the steps of:
forming an oxidation resistant coating made of a MCrAlY alloy on a surface of a base material; and
forming a hard wear resistant coating on a surface of the oxidation resistant coating.
9. The contact surface manufacturing method according to claim 8 , further comprising the steps of:
forming an oxidation resistant coating on a blade surface of the turbine rotor blade after the step of forming the hard wear resistant coating; and
performing tip brazing, a stabilization treatment, and a thermal diffusion treatment after the step of forming the oxidation resistant coating on the blade surface of the turbine rotor blade.
10. The contact surface manufacturing method according to claim 8 , further comprising the step of forming an oxidation resistant coating on a blade surface of the turbine rotor blade before the step of forming the hard wear resistant coating.
11. The contact surface manufacturing method according to claim 8 , wherein:
the turbine rotor blade is a used turbine rotor blade; and
the contact surface manufacturing method further comprises the step of removing a used contact surface on a surface of the contact block before the step of forming the oxidation resistant coating.