Laser powder welding repairs turbine blades at less cost

摘要

A laser powder welding technology in which directionally solidified or monocrystalline structures can be reproduced on gas turbine hot section components has been reported by Sulzer Elbar, a subsidiary of Sulzer Turbomachinery Services, The Netherlands. The technology is said to combine traditional welding and cladding techniques with low distortion and good dimensional control. The process is based on a digital model of the part and on CNC control of the laser welder. The laser beam melts the area to be repaired, and an inert gas stream carries the powder particles to the weld pool. The substrate acts as a heat sink, enabling rapid cooling of the melt pool. Deposition rates can reach 90 g/min, and thickness ranges from 0.5 to 1 mm with widths from 0.5 to 5 mm.