Electromagnetic methods can be used to affect the solidification of metallic alloys. Combined alternating and static (DC) magnetic fields can induce pressure waves in liquid metals in a contactless manner, refining grain structure, preventing component segregation, and dispersing added particles. Here, the possibility of using a pulsed magnetic field in combination with a DC magnetic field to improve the solidification structure of metals is investigated. This enables achieving higher pressure amplitude and liquid movement within the whole crucible volume at the same power consumption. This can be a prospective way to achieve a fine-grained and a more homogeneous microstructure of metallic alloys as well as disperse added particles. In this work, analytical description of the phenomena and numerical modeling of the pressure amplitude and melt motion has been performed. A series of experiments have been carried out to demonstrate the effect of such interaction on the solidified metal microstructure. It is found that a combination of pulsed and DC magnetic fields creates strong compression and expansion of the liquid metal. Metals solidified under such interaction exhibit finer grain structure in Sn-Pb alloy and improved TiB₂ particle distribution in 6061 aluminum alloy.

Electromagnetic systems designed for liquid metal transportation offer a wide range of promising applications within the metallurgical industry. Among these systems, permanent magnet pumps stand out due to their remarkable advantages in processing liquid aluminum. These pumps enable the generation of a vigorous flow of liquid metal, all while maintaining a non-contact approach by bypassing the insulating walls. In this study, we investigate the flow of liquid metal in a rectangular cross-section channel created by a permanent magnet pump. To comprehensively analyze the flow characteristics and assess the technology's scalability, we employ order of magnitude evaluations alongside an experimental model. Ultrasound Doppler velocimetry is utilized to measure the velocity distribution, which reveals an intriguingly asymmetric flow pattern. Furthermore, additional measurements are conducted to determine the integral flow rate and pressure difference. Remarkably, the numerical simulations align closely with the experimental results, demonstrating good agreement in the p-Q curves. These findings provide substantial evidence supporting the remarkable potential of this technology in various applications, such as aluminum degassing, particle agglomerate dispersion, and efficient transportation.

Degassing of aluminium alloys is an important technological step. In this work the idea and mathematical, and numerical description of electromagnetic aluminium degasser is presented. Experimental electromagnetic device for degassing aluminium alloys is designed and tested to estimate the feasibility of this technology. Degassing is a technological intermediate step in the production of aluminium between the melting and casting of the metal. Mainly hydrogen has been dissolved in liquid aluminium because of reaction with water vapor. To prevent the formation of pores during casting, hydrogen is removed - the liquid metal is degassed. Typically, degasification is achieved by injecting an inert gas in the metal, usually argon, which binds to hydrogen bubbles. For the industrial process to be more efficient, the size of the argon bubbles must be as small as possible. At present, the most widely used method to refine bubbles is to place a mechanical rotor inside the liquid metal. Although such mechanical bubble shredding fulfils the task, it also has significant disadvantages, hence alternatives are being sought.

Promocijas darbā tika pētīti elektromagnētiskās indukcijas sūkņi ar pastāvīgajiem magnētiem, kas piemēroti lietojumam metalurģijā.

Electromagnetic induction pumps with permanent magnets, suitable for use in metallurgy, have been studied in the Doctoral Thesis