| Electromagnetic casting (EMC) is a new material processing method, a comprehensive subject based on magnetohydrodynamics and combined with metallurgical engineering. The outstanding merits of EMC lie in its high smooth surface, good mechanical properties and high production efficiency.In this paper, the engineering application of EMC technology in our country has been respected and its theory and technology process has been systematically researched. The main results are as follows:1. A physical model of equivalent circuit has been built based on the electromagnetic field theory. The electric parameters such as inductor current, power frequency and energy consumption etc. have been preliminarily estimated. As a result, a pilot plant of EMC is established.2. The stability and molding of semi-levitated liquid column is a key to the success of EMC. Based on the Kaiser and Russia types usually used abroad, by the method of detail experimental combined the simulation of magnetic intensity distribution and liquid column shape analysis, a special arc inductor has been designed to ensure the formation of the semi-levitated liquid column, whose side is vertical and surface is stable. All these results provided the foundation for the EMC of Aluminum alloy.3. A specific layered isolating method has been used to measure the temperature and its gradient distribution of simulated ingot. Based on the results above, the induced current intensity distribution and the induced heating rate within the EMC slab has been calculated according to the Joul-Lenzs laws. Moreover, the temperature field within EMC ingot has been numerically simulated . To provide the choice basis for the technology parameters, the pouring temperature, cooling intensity and position has been studied to investigate their influence on the casting speed, liquid column height and shape. The calculated results coincide well with the measured ones.4. In the first time, a coupled model of mutual inductance has been used to simulate the electromagnetic field of EMC slab. The influence of inductor shape, inductor current intensity, screening positions and power supply frequency et al on the magnetic intensity distribution has been researched. The calculated results of the semi-levitated liquid column shape under loading coincide well with the experimental results.5. To get the matching relation between casting speed and key technology parameters such as pouring temperature, column height and cooling water flow, adetail technology process has been investigated during EMC aluminum alloy. A rational cooling intensity distribution has been used based on the theory analysis, temperature field measurement as well as casting experiments. A good floating controller has been designed to solve the difficult problems of pouring and liquid level control during EMC. Pure aluminum and 3004 aluminum alloy slabs (520 X 130x900mm) as well as 2024, 5182, 6063 aluminum alloy billets ( 174X 1000mm) have been cast successfully in our domestic pilot plant.6. The technology investigation of electromagnetic casting for a double-ingot have been carried out, based on analysis of the key parameters, the double-ingot with size of 260mm was cast simultaneously.7. The surface and inner qualities of EMC slab have been investigated and compared with those of the direct casting (DC) one. The results show that the surface roughness of EMC slab reaches up to Ra 0.65 m ( 7- 8). It is also found that the macrostructure of EMC slab is composed of fine, uniform, equiaxed grains so that its tensile intensity increases by 25-27% and toughness increases by up to 20-200% than the DC slab.8. A hot top EMC subject of aluminum thin strip has been put forward in the first time according to its characteristics. Its principle lies in the control of the liquid column, which has been controlled separately. 1) On the top zone of liquid column, a hot top made of special screen and refractory material is used to confine the liquid column, solving the problems of pouri...
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