What are the properties and application characteristics of the abradable sealing metal-ceramic composite powder

       Cermet grindable and sealable composite powder, the core material of which is soft, light, brittle or easy to scrape non-metallic particles, such as graphite, diatomite, bentonite, hexagonal boron nitride, ZrO2, etc. Hot alloy cladding. Optional cladding metals and alloys include cobalt, nickel, nickel-chromium (NiCr), nickel-chromium-aluminum (NiCrAI), copper, aluminum, aluminum-silicon alloys, and the like. Coatings are generally prepared by a plasma spray process.



    (1) Nickel (or copper) clad graphite (Ni/C) composite powder can be used to prepare loose, porous, soft and abradable sealing coatings for working conditions below 480 °C, such as low temperature end of aero-engine compressors (<480℃) The volute is sprayed to wear the sealing coating.

    (2) Nickel-coated diatomite (Ni/DE) composite powder can be used as abradable sealing coating at higher temperature (800℃~900℃), such as spraying on the inner surface of the volute of the compressor of aero-engine The abradable seal coating is scraped by the high-speed rotation of the rotor blades during operation to form and control the radial clearance of the compressor.

    (3) Aluminum-silicon-boron nitride (AlSi-BN) composite powder can be used to prepare wearable sealing coatings on metal substrates such as AI, Mg, and Fe in the temperature range of -196°C to 350°C. For example, it is used in all-gear transmission centrifugal air compressors for air separation, which can improve the efficiency of the compressor and reduce energy consumption.