Liburdi Powder Metallurgy (LPM®), is a patented high strength process used in the manufacture and repair of turbine blades, vanes and other superalloy turbine components. LPM® provides superior strength and performance compared to conventional diffusion braze and weld repair methods.
LPM® powder metallurgy compositions can be used to repair virtually all nickel and cobalt superalloys and can be manufactured and applied as either flexible tapes of varying thickness or as a moldable putty for cavities or fillets.
Damaged areas are first removed by grinding similar to preparation for welding. Then new LPM® material in putty or tape form is applied to fill the area — the part is then processed through specialized vacuum heat treatments and machined or blended to the final dimensions.
LPM® uses powder alloys of superalloy nickel composition to produce high strength and fatigue resistant repairs. Repair limits can now be extended to higher stressed areas which were not previously repairable.
Special formulations are also available for high performance blade tips – using oxidation resistant alloys combined with abrasive particles.
Structural areas can now be repaired with LPM® alloys exceeding the vane material strength and without the distortion caused by welding. LPM® can also be used to build-up and restore thin airfoil and shroud seal surfaces that have eroded in service. Many vanes experience major cracking in the high stress fillet areas which are not effectively repaired using conventional weld repair.
These same parts, after repair with higher strength LPM®, are providing reliable service and out-performing conventional weld repairs. The LPM® process is approved for Aircraft, Aeroderivative and Heavy Duty Frame components.