US 5,956,845 A · Method of repairing a turbine engine airfoil part

Abstract

A method of forming an engine airfoil part. The attributes of a final workpiece product are selected. An appropriate substrate composition is determined depending on the selected attributes. A workpiece substrate is formed to near-finished dimensions. An appropriate coating material composition is determined depending on the selected attributes. The workpiece substrate is prepared for a high-density coating process. The high-density coating process, such as HVOF thermal spray, is performed to coat the workpiece substrate with the coating material. The coating material is built-up to a thickness effective to obtain desired finished dimensions after performing a hot isostatic pressing treatment. The appropriate hot isostatic pressing treatment parameters are determined. The hot isostatic pressing treatment is performed on the coated workpiece substrate to obtain a metal product having the desired finished dimensions and diffusion bonding between the coating material and the workpiece substrate.

Claims22

Dependent claims

A method of repairing a turbine engine airfoil part, comprising the steps of:

cleaning a turbine engine airfoil part, the turbine engine airfoil part having a substrate being comprised of a metal alloy;
welding eroded portions of the turbine engine airfoil part using a weld material comprised of the metal alloy, the welding producing weld witness lines;
grinding flush the weld witness lines to prevent blast material from becoming entrapped in the weld witness lines;
masking portions of the turbine engine airfoil part that are not to be HVOF sprayed;
recleaning the turbine engine airfoil part in preparation for HVOF spraying;
HVOF spraying the turbine engine airfoil part using a coating material comprised of the same metal alloy as the substrate so as to build up a cordal dimension of the turbine engine airfoil part to a thickness greater than the thickness of an original cordal dimension of the turbine engine airfoil part;
hot isostatic pressing treating the turbine engine airfoil part to eliminate voids between the turbine engine airfoil part substrate, the weld material and the coating material and to obtain diffusion bonding between the substrate and the coating material;
and selectively removing portions of the HVOF spray material to finish the turbine engine airfoil part to the original cordal dimension.

5 more elements

A method of repairing a turbine engine airfoil part, comprising the steps of:

cleaning a turbine engine airfoil part, the turbine engine airfoil part having a metal alloy substrate;
welding eroded portions of the turbine engine airfoil part using a weld material comprised of the metal alloy, the welding producing weld witness lines, grinding flush the weld witness lines to prevent blast material from becoming entrapped in the weld witness lines;
masking portions of the turbine engine airfoil part that are not to be coated with a high density coating;
recleaning the turbine engine airfoil part in preparation for high density coating;
determining dimensional differences between pre-repaired dimensions of the turbine engine airfoil part and desired post-repair dimensions of the turbine engine airfoil part;
determining a build-up thickness of high density coating material required to obtain the desired post-repair dimensions of the airfoil part;
performing a high-density coating process;
performing a hot isostatic pressing treatment to eliminate voids between the turbine engine airfoil part substrate, the weld material and the coating material and to obtain diffusion bonding between the substrate and the coating material;
and selectively removing portions of the HVOF spray material to finish the turbine engine airfoil part to the desired post-repair dimensions.

6 more elements

A method of repairing a turbine engine airfoil part, comprising the steps of:

determining dimensional differences between pre-repaired dimensions of a post-inspection turbine engine airfoil part and desired post-repair dimensions of the turbine engine airfoil part, the pre-repair airfoil dimensions having different airfoil characteristics than the post-repair airfoil dimension, the turbine engine airfoil part having a substrate comprised of a superalloy;
determining a build-up thickness of coating material required to obtain the desired post-repair dimensions of the turbine engine airfoil part;
performing a high-density coating process to coat the turbine engine airfoil part with a coating material to build-up a thickness of coating material effective to change the airfoil characteristics of the turbine engine airfoil part and obtain desired post repair dimensions after performing a hot isostatic pressing treatment, the coating material comprising a metal alloy capable of forming a diffusion bond with the substrate;
and then performing the hot isostatic pressing process to obtain a post-repair turbine engine airfoil part having the desired post-repair dimensions and having diffusion bonding between the coating material and the turbine engine airfoil substrate.

1 more element

A method of repairing a turbine engine airfoil part, comprising the steps of:

cleaning a turbine engine airfoil part, the turbine engine airfoil part having a substrate being comprised of a metal alloy;
determining if eroded portions of the turbine engine airfoil part require welding repair;
welding eroded portions of the turbine engine airfoil part determined to need welding repair using a weld material comprised of the metal alloy, the welding producing weld witness lines;
grinding flush the weld witness lines to prevent blast material from becoming entrapped in the weld witness lines;
masking portions of the turbine engine airfoil part that are not to be high density coated;
recleaning the turbine engine airfoil part in preparation for high density coating;
high density coating the turbine engine airfoil part using coating material comprised of the same metal alloy as the substrate so as to build up a cordal dimension of the turbine engine airfoil part;
hot isostatic pressing treating the turbine engine airfoil part to obtain diffusion bonding between the substrate and the coating material;
and selectively removing portions of the high density coating to finish the turbine engine airfoil part to desired dimensions.

6 more elements

Dependencies are inferred from the claim text.

Method of repairing a turbine engine airfoil part

Life of this patent

Method of repairing a turbine engine airfoil part

Life of this patent

Abstract

Claims22