MightyLev: An acoustic levitator for high-temperature containerless processing of medium to high-density materials

‘MightyLev’, a new multi-emitter ultrasonic acoustic levitation device capable of extremely stable levitation of materials of density up to at least 11.3 gcm−3, is described. The exceptional stability of medium to high-density samples levitated in MightyLev makes the device highly suitable for chemical and structural analysis using micro-focused spectroscopic and X-ray scattering techniques. In combination with mid-infrared laser heating, MightyLev is capable of levitating metallic and oxide materials during high-temperature cycling and melting above 1500 K. Instabilities in particle confinement during heating were investigated by directly visualising the acoustic field using schlieren imaging. The results reveal jets of hot-air directed along the anti-nodes of the acoustic field. The reaction force on the sample from the jet, coupled with the restoring force of the acoustic trap, generates a parametric lateral oscillation of the sample. This result provides valuable insight for future optimisation and wider application of acoustic levitation for high-temperature containerless materials processing.