The Study On Purification Of Aluminum Alloy Under High-frequency Magnetic Field

With the development of science and technology, an increasingly important role played by the aluminum alloy has many advantages in society. Aerospace, automobile manufacturing, high-speed rail passenger are important areas ofapplication. This makes a higher demand on the quality of aluminum alloy. Aluminum alloy in the production process can easily produce hydrogen holes andnon-metallic inclusions and other defects, affecting the integrated performanceof the alloy. using high frequency electromagnetic purification technology to purify the alloy melt, compared with the conventional purification methods havehigh purification efficiency, do not pollute the alloy melt, applying a magneticfield to facilitate purification effect, etc. In this paper, I carried out some research on the purification of Al-Si alloy melt using high frequency magnetic field.This article optimized the design of a high frequency induction coil, On this basis, the measurement and analysis of the distribution of the axial-radialmagnetic field strength within the magnetic induction coil with or without load.Studied how the alloy melt temperature, separator diameter, the influence of the electromagnetic field time and the purification of the current size to influence the separation of inclusions with Al-18%Si alloy. The results showed that:Purification works best when the melt temperature of620~640℃, Temperature is too low, the melt viscosity is high; Temperature is too high, The conductivity of the aluminum melt decreased so that the electromagnetic driving force smaller Affects the purification effect; The size of the separator diameter can significantly affect the purifying effect, Under the same conditions, Separation of small diameter purifying effect is better. With the diameter increasing needs a long pipe diameter purification time or higher magnetic induction intensitycan effectively remove the inclusion. Effect changed for the better with longertime. The separation time is long, Non-metallic inclusions in molten metal have enough time separation from the melt; Purifying effect change with the increase in the intensity of magnetic induction. However, the magnetic flux density is too large will be seriously turbulent melt. Make purification effect becomespoor.This article Adopted the high frequency magnetic field to attempt to verificatythe Al-18%Si alloy purifying effect. Measured by EDS analysis and Measuredmicrohardness. Investigated and analysis of the primary silicon size and shape as wellas distribution in the cross section of alloy samples. The results show that: Throughthe electromagnetic force alloy samples of silicon content in the specimen core part isvery low. The content of silicon element greatly improved until the sample thesegregation, the size of primary silicon are big in this area. Its hardness was lower inthe middle and was higher in Segregation area. This article also did purificationexperiment with Al-Si alloys containing2%Al2O3particles, Achieved goodseparation effect. That fully proved the superiority of high-frequency electromagneticpurification technology.