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What are transonic airfoils, and what is the active clearance control? Check out our technical dictionary and find out more about engine technology terms – from active clearance control to velocity triangle. Laser drilling Laser powder cladding Limiting Mach number Linear friction welding Low-pressure compressor Low-pressure turbine Low-pressure plasma spraying (LPPS)Low-pressure plasma spraying (LPPS)
Contrary to atmospheric plasma spraying the low-pressure plasma spraying process is performed in a vacuum chamber at a pressure of approx. 40 - 100 hPa. Component and torch are moved with special manipulators capable of being exposed to the very fine metal dusts and high operating temperatures. A charging system is frequently used to load the components to be coated into the facilities.Characteristic features of LPPS:
- oxide-free metallic coatings
- dense pre-free coatings
- high adhesive strength of metallic coatings (> 250 MPa)
- no limitations as to the coating thickness, i.e. thicknesses may vary between 0.05 mm and several millimeters
Major applications of LPPS:
- corrosion and oxidation protection coatings, type McrAlY (M = Co, Ni, Ni Co) on turbine parts
- high-temperature metallic wear protection coatings, type Stellite and Tribaloy
- gas seals in the turbine area, type McrAlY)
- dimensional correction and repair coatings from high-temperature and wear-resistant alloys as well as from the substrate material
- corrosion-resistant bond coats for thermal barrier coatings.