Design And Experimental Study Of Containerless Device Based On High Frequency Electromagnetic-Ultrasonic Mixed Levitation

With the rapid development of materials science,the requirements of the material performance increases greatly,therefore,more new materials are needed to be developed.Containerless technology has some unique characteristics and it has obvious advantages in the development of new materials.The paper presents a method using mixed levitation of high-frequency electromagnetic with ultrasonic standing wave to carry out the containerless process of materials on the basis of the previous researches and characteristics of various containerless technologies.For the sake of the purpose of the experiment,and with the aid of ANSYS software,the combination of the radiation end and the reflection end of different concave spherical radii is simulated and analyzed,and through the simulation experiment and analysis,the paper founds out the better combination of the radiation end and the reflection end which can provides great sound pressure.In order to make the levitation position in the ultrasonic standing wave levitation coincides with the levitation position in the electromagnetic levitation and adjust the reflection end in the mixing experiment,the electronic control platform is designed.According to the theory of levitation force to which the spherical samples is subjected in multi-turn coils,the paper used MATLAB software to carry out the simulation analysis of several types of induction coil that in common use,and the relationship between the structural parameters and the levitation force of various types of coils was obtained through the simulation,the results indicate that the levitation force of the four types of coils nonlinearly decrease with the increase of the initial turn radius,the number of stable coil turns,the half coil angle of the suspension coil and the half cone angle of the stabilizing coil;and nonlinearly increase with the increase of the plane spacing,the coil turns spacing and the turn number of the suspension coil;the levitation force provided by the cylindrical coil is generally greater than that of the spiral coil.The paper used MAXWELL software to carried out the simulation analysis of the electromagnetic vortex field of the type four induction coil,and the calculated electromagnetic eddy current field was use as the heat source of the transient temperature field analysis in the ANSYS software.The simulation results show that the maximum temperature of the suspended sample decreases with the increase of the number of stable coils,the half-taper angle of the suspension coil and the half-taper angle of the stabilizing coil,and the maximum temperature of the suspended sample increases with the increase of the suspended position,that is,the sample temperature at the bottom of the coil is higher than that at the other position;the maximum temperature of the suspended sample increase first and then decrease with the increase of the sample radius.The effect of the initial turns radius,plane spacing,turn pitch,and stable coil turns on the maximum temperature of the sample is relatively small.In addition,through the experimental verification,the experimental results are in accordance with the simulation results.The relationship between the structural parameters of the induction coil and the size as well as the stability of the experimental sample wasobtainedthrough the experiment.The experimental results indicate that the larger taper angle(in a certain range)with the smaller diameter result in the betterstability of the experimental sample in the type four levitation.In this paper,a high frequency electromagnetic and ultrasonic standing wave mixed levitation system is designed.The system includes five parts: ultrasonic standing wave levitation device,high frequency electromagnetic levitation device,circulating water device,argon atmosphere device and electronic control platform.Low melting tin samples and high melting aluminum samples respectively were melted and cooled to solidify in the air and argon atmosphere,enabling the metal to be completely free of containers during the melting and cooling solidification process.