LSR™ - Liburdi Slurry Recoatings

The Liburdi slurry recoating (LSR™) process deposit plain and modified aluminide coatings on internal and external surfaces of turbine hardware for oxidation (corrosion) protection. These coatings exhibit microstructures, chemistries, and cyclic oxidation stabilities as good as or better than conventional aluminide coatings

The quest for increased efficiency has resulted in higher operating temperatures for gas turbine hot section components, and thus faster rates of degradation for both internal and external components.

LSR™ provides numerous benefits, including

• Ease of use.
• A large variety of possible coating chemistries, using blends of Si, Cr, Pt, and Y, or alloys of these elements
• The process can easily be incorporated into new manufacturing and repair facilities to reduce turbine production and overhaul cost and delivery time.
• Typically used for both internal and external coatings. For internal components, the slurry is injected.
• Can be implemented and run safely in component manufacturing or overhaul facilities, thus reducing manufacturing and overhaul time and costs.
• Provides a green alternative to chrome 6 or other environmentally unfriendly metals.

The LSR™ process was introduced into service in 1999, and some of those aircraft now have over 40,000 hours of operational time on them. The process has been used on:

• Avon HP, IP, LP,
• RB211-24C HP
• Frame 7 1st and 2nd stage buckets

LSR™ Process

The LSR™ slurry is a mix of metal particles with a binder and solvents. The slurry uses no chlorine, fluorine, sulphur, phosphorous, sodium potassium, zinc, copper, boron or any other element that could compromise coating performance.

Slurry is introduced into passages by dipping or injection. Thickness is governed by surface tension and viscosity.

LSR™ recoatings can diffuse into existing coatings, which means that the process is extremely useful for touch-ups and repairs. Older coatings can be renewed with a single layer of Si-aluminide without stripping the original coating. This diffusion characteristic means that LSR™ can also be used as an overlay coating on MCrAlY coatings.

The process can be customized to replace any simple Si-, Cr-, or Pt-modified aluminide coating technology on Ni, Co, or Fe base alloys.

LSR™ PtAl coatings can be tailored to use platinum only in the areas that exhibit high temperature degradation and selectively protect the critical surfaces.  This tailored approach to selectively coated form for function saves the operator significant costs in the use of the precious metal. 

Learn more about LSR™ green turbine coatings

   View the LSR™ datasheet.