ABSTRACT
This chapter describes the containerless processing of Nd123 and yttrium iron garnet by aero-acoustic levitation. Nucleation and phase selection in the deeply undercooled melt have been investigated in order to establish the conditions for direct growth of the peritectic phases by containerless processing. The chapter focuses on solidification of the peritectic phase in levitated droplets. The aero-acoustic levitation experimental setup combined with a CO2 laser irradiation system was used for the undercooling experiments. The aero-acoustic levitator has been developed for levitating and heating electrically nonconductive materials, such as glass, ceramics and other chemically reactive materials. Solidification was allowed to occur without any intervention, i.e. nucleation was allowed to take place spontaneously in the melt during cooling, followed by recalescence and completes solidification. In other cases, solidification was forced to occur by seeding the melt by inserting a single crystal at a controlled undercooling, followed again by recalescence and complete solidification.
