In order to optimize technological parameters and realize directional solidification,temperature fields of cold crucible continuous melting and directional solidifying Ti50Al（mole fraction,%） at different parameters were calculated.Continuous casting of the model is achieved by distinguishing the moving unit at different positions.The calculation results show that the feeding rod is entirely melted at 200 s,the melt of feeding rod has some superheat degree at 300 s under the conditions of 52 kW and 3.0 mm/min.Both the superheat degree and the molten zone of the feeding rod reduce,the solid-liquid interface becomes concave with increasing velocity from 1.2 mm/min to 6.0 mm/min when the power is 52 kW,and the outside layer of the rod cannot be melted at the velocity of 6.0 mm/min.Both superheat degree and the molten zone of the feeding rod increase,the solid-liquid interface descends and becomes concave with increasing power from 48 to 58 kW at velocity of 3.0 mm/min,and the rod cannot be melted entirely when the power is 48 kW.Cold crucible continuous melting and directional solidification of TiAl alloys will be achieved successfully when the pulling velocity and the power are matched appropriately.
To improve the power efficiency and optimize the configuration of cold crucible using for continuous melting and directional solidification （DS）, based on experimental verification, 3D finite element （FE） models with various configuration-elements were developed to investigate the magnetic field in cold crucible. Magnetic flux density （B） was measured and calculated under different configuration parameters. These parameters include the inner diameter （D2）, the slit width （d）, the thickness of crucible wall, the section shape of the slit and the shield ring. The results show that the magnetic flux density in z direction （Bz） both at the slit and at the midpoint of segment will increase with the decrease of D2 or with the increase of the width of the slit and the section area of wedge slit or removing the shield ring. In addition, there is a worst wall thickness that can induce the minimum Bz for a cold crucible with a certain outer diameter.
