One method utilized involves allowing the tips of the turbine blades to wear into a rub tolerant surface on the casing. This ensures that when the blades are fully extended due to centrifugal forces during engine operation, only a minimal leak path will exist for the hot gas across the tips of the blades.

In order to minimize blade tip wear, engine manufacturers are now designing blade tips with wear resistant coatings. VAC AERO has developed a HVOF CoCrAlY coating that fulfils this application.

Blade tips sprayed with HVOF CoCrAlY.  Metal mask set up is shown.	Micrograph showing HVOF CoCrAlY on blade tip (overspray is also shown).
Blade tips sprayed with HVOF CoCrAlY.	Micrograph showing HVOF CoCrAlY on blade tip.

For more information please visit our Coatings page.