Investigation of high efficient supersonic nozzle parameters for tin powder production by gas atomisation


ÜNAL R. , Aksoy A.

European Powder Metallurgy Congress and Exhibition, Euro PM 2005, Prague, Çek Cumhuriyeti, 2 - 05 Ekim 2005, cilt.2, ss.23-29 identifier

  • Yayın Türü: Bildiri / Tam Metin Bildiri
  • Cilt numarası: 2
  • Basıldığı Şehir: Prague
  • Basıldığı Ülke: Çek Cumhuriyeti
  • Sayfa Sayıları: ss.23-29

Özet

Atomization can be defined simply as the break up of liquid into fine droplets, typically smaller than about 150 microns. In a typical gas atomization process, the molten metal stream flows from the bottom of a heated tundish through a melt feed tube into the atomization zone. Here, the liquid is disintegrated into a collection of liquid droplets as it encounters a high velocity gas stream just below the exit of the melt orifice. The most important parameter for production of fine powders is the velocity of atomizing gas. This can be achieved by increasing the pressure, but this way will not be economic. For that reason supersonic nozzles are used in close coupled configuration for an efficient atomization. In this study, a new supersonic nozzle was designed and produced. Using this supersonic nozzle in close coupled system tin powder was produced at different operating conditions. The results showed that the increasing the gas pressure up to 3.5 MPa reduced the powder size down to median powder size of 32 microns. Powders are spherical in shape and have smooth surfaces.