Superalloy laser cladding with surface topology energy transfer compensation

Abstract

A superalloy substrate, such as a turbine blade or vane, is fabricated or repaired by laser beam welding to clad one or more layers on the substrate. Laser optical energy is transferred to the welding filler material and underlying substrate to assure filler melting and adequate substrate surface wetting for good fusion. Energy transfer is maintained below a level that jeopardizes substrate thermal degradation. Optical energy transfer to the filler and substrate is maintained uniformly as the laser beam and substrate are moved relative to each other along a translation path by varying the energy transfer rate to compensate for localized substrate topology variations.

Description

[0001] Cross references to related applications [0002] This application incorporates by reference the joint co-pending US invention patent application with the assigned serial number 13 / 611144 and the attorney case number 2012P09234US entitled "LASER CLADDING SYSTEM FILLER MATERIAL DISTRIBUTION APPARATUS". Technical field [0003] The present invention relates to a method of cladding superalloy parts such as turbine blades and buckets whose operation is degraded by laser beam welding. More specifically, the method of the present invention welds one or more layers of filler material to the substrate along the welding translation path, and adjusts the laser energy to compensate for local substrate topology changes, thereby promoting uniform or intentional modification along the path Energy transfer rate. Background technique [0004] The "structural" repair of gas turbines or other superalloy parts is generally considered to replace damaged materials with matching alloy materials a...

AI Technical Summary

Problems solved by technology

This results in over-melting, over-heating and over-stressing of the crack-sensitive substrate material 40 (unnecessarily causing subsequent thermal and / or strain-age cracking)

Images