“Stirring” is a very important measure when doing smelt process. The quality of the billet is directly determined by the consistency of stirring. Normally have hand stirring, gas stirring, mechanical stirring, electromagnetic stirring, etc. And the electromagnetic stirring is gradually popularized as its stirring efficiency and simple operation.
Induction electromagnetic stirring device is a device which use the electromagnetic induction principle to create a magnetic field to act on a regular motion for the aluminium liquid. By changing the direction and intensity of the traveling wave magnetic field, it can effectively adjust the stirring intensity and stirring direction to the aluminium liquid。
The inner wall of the furnace use the refractory materials importing from UK(Morgan). It is poured in a kind of concrete operation, not made by firebrick like general operation.
1. Fast heat conduction which means a shorter time to arrive a uniform temperature.
Reduce the pollution caused by refractory ash
3. Small surface porosity, not sticky, no residue, easy to clear; no pollution; Furnace+Electromagnetic Stirring.
Advantage of Furnace+Electromagnetic Stirring：
1. Improve the isothermality performance of the furnace, general furnace upper and the lower temperature 30℃-50℃, the difference after electromagnetic stirring is 5℃-10℃.
2.Uniform distribution with alloy element.
GLM has cooperated with Shanghai Jiaotong University to study the Global First Aluminium Liquid Electromagnetic Purification system. The electromagnetic purification utilizes the external electromagnetic field to promote the separation of impurities, combining with the adsorption ability of the ceramic separator, it can achieve to remove the fine impurities efficiently and steadily. As the driving force of the electromagnetic separation is mainly depend on the conductivity difference between impurities and melt, there is no relationship to the density, chemical composition, condition(solid, liquid or gas) , it makes Electromagnetic Purification has unique advantages in removing impurities in aluminium melt. This is because that the oxide impurities generally suspend in the melt, as its large superficial area , irregular shape and may adsorbed gas. Also impurities and melt density are not much different, it is difficult to remove the impurities by natural sedimentation, floating or centrifugation. After use the plate filter and electromagnetic purification system, the impurities content was further reduced, especially the impurities which is less than 10μm
In the casting process, after 5 minutes of discharge, about 160kw power, take the first group of samples before and after the electromagnetic purification flow through, mark as before1 and after1; After 30 minutes, about 80kw power, take the second group samples, mark as before2and after2. Use the image analysis software to calculate the average area fraction, quantity and size distribution of nonmetal impurities. Results see below: