Airfoils with improved oxidation resistance and manufacture and repair thereof

A method for repairing a gas turbine airfoil, said method comprising:

• a. providing an airfoil comprising a wall, said wall defining the perimeter of said airfoil and comprising a leading edge section and a trailing edge section, and further comprising a first material with a melting temperature and an oxidation resistance;
• b. removing at least one portion of said wall, said at least one portion located in at least one section of said wall selected from the leading edge and the trailing edge;
• c. providing a second material, said second material having an oxidation resistance that is greater than the oxidation resistance of the first material and a melting temperature that is at least about 83° C. (about 150 degrees Fahrenheit) greater than the melting temperature of said first material, wherein said second material comprises a material selected from the group consisting of Rh, Pt, Pd, and mixtures thereof, and wherein said second material further comprises a metal selected from the group consisting of Ir, Ru, and mixtures thereof, at a level of up to about 5 atomic percent;
• and
• d. disposing said second material onto said wall in the at least one section where said at least one portion of said wall was removed.

A method for repairing a gas turbine airfoil, said method comprising:

• a. providing an airfoil comprising a wall, said wall defining the perimeter of said airfoil and having a cross-sectional wall thickness, said wall comprising a leading edge section and a trailing edge section, and further comprising a nickel-based superalloy;
• b. removing at least one portion of said wall, said at least one portion located in at least one section of said wall selected from the leading edge section and the trailing edge section;
• c. providing a material in the form of a freestanding insert, said material selected from the group consisting of Rh, Pt, Pd, and mixtures thereof and further comprising a metal selected from the group consisting of Ir, Ru, and mixtures thereof, at a level of up to about 5 atomic percent;
• d. disposing said material onto said wall at the at least one section where said at least one portion of said wall was removed such that said material comprises from about 0.13 mm (about 0.005″) to about 0.64 mm (about 0.025″) of said cross-sectional thickness of said wall;
• and
• e. heat-treating said airfoil.

A method for manufacturing a gas turbine airfoil,

• said airfoil comprising a wall, said wall having a cross-sectional thickness that is specified to a nominal dimension, said wall defining the perimeter of said airfoil and comprising a leading edge section and a trailing edge section, and further comprising a first material with a melting temperature and an oxidation resistance;
• said method comprising:
• a. providing an airfoil with a deficit in cross-sectional wall thickness, relative to said specified nominal cross-sectional wall thickness dimension, in at least one section of said wall, said section selected from the leading edge section and the trailing edge section;
• b. providing a second material, said second material having an oxidation resistance that is greater than the oxidation resistance of said first material and a melting temperature that is at least about 83° C. (about 150 degrees Fahrenheit) greater than the melting temperature of said first material, wherein said second material comprises a material selected from the group consisting of Rh, Pt, Pd, and mixtures thereof, and wherein said second material further comprises a metal selected from the group consisting of Ir, Ru, and mixtures thereof, at a level of up to about 5 atomic percent;
• and
• c. disposing said second material onto the wall at said at least one section such that said deficit in cross-sectional wall thickness is eliminated.

A method for manufacturing a gas turbine airfoil,

• said airfoil comprising a wall, said wall having a cross-sectional thickness that is specified to a nominal dimension, said wall defining the perimeter of said airfoil and comprising a leading edge section and a trailing edge section, and further comprising a nickel-based superalloy, said method comprising:
• a. providing an airfoil with a deficit in cross-sectional wall thickness relative to said specified nominal cross-sectional wall thickness dimension, in at least one section of said wall, said section selected from the leading edge section and the trailing edge section;
• b. providing a material selected from the group consisting of Rh, Pt, Pd, and mixtures thereof and further comprising a metal selected from the group consisting of Ir, Ru, and mixtures thereof, at a level of up to about 5 atomic percent;
• c. disposing said material onto the wall at said at least one section such that said second material comprises about 0.13 mm (about 0.005″) to about 0.64 mm (about 0.025″) of said cross-sectional thickness of said wall and such that said deficit in cross-sectional wall thickness is eliminated;
• and
• d. heat treating said airfoil.