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.

Use of permanent magnet systems for metallurgical applications have been proposed before. We have continued development of such systems by investigation use of single magnetic dipole which is realized as permanent magnet cylinder. Magnet is magnetized orthogonal to its axis and has been mounted to the side of the liquid metal reservoir. System first was modelled using small scale experiment with galinstan melt. Velocity distributions and flow patterns in reservoir using Ultrasound Doppler Anemometer were acquired and will be presented here. Additionally, numerical model using Comsol and Cenos modelling software were developed alongside analytical, non-dimensional estimation calculations. Experimental results were used to adjust and verify calculations. Using these calculations, industrial scale system was modelled and designed, and built. Industrial prototype was installed to 20t aluminium remelting furnace in Norway. It demonstrated that sufficient flow for efficient stirring could be achieved, while power of unit did not exceed 2kW, what is up to 30 times less than for comparable size classical EM stirrers with current windings. Besides system allows unique versatility by changing tilt angle to change flow pattern continuously allowing adaptive melting process, and costs significantly less than classical systems. By the time of the conference another prototype will be commissioned and results will be included.

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.

The rise of metal additive manufacturing technology has increased the demand for high-performance alloys such as metal matrix composites (MMCs). The metallurgical production of MMCs remains a challenge. The nano-powder of dielectric particles does not mix well into the liquid metal because of several reasons. On a macroscopic level, the powder is rejected by the molten metal through buoyancy and surface tension forces. On a microscopic level, the particles are held together by Van der Waals forces forming particle agglomerates. Our research strategy is to address these issues separately in two steps. We are investigating an electromagnetically assisted MMC casting method for the production of particle-strengthened, directionally solidified aluminum alloys. In the first step, nanoparticles are mixed into melt while it is in a semi-solid state by efficient permanent magnet stirrers. Then, the alloy is subjected to ultrasound treatment for fine particle dispersion. Semi-continuous casting of MMC is used to obtain material for additive manufacturing process. Material is cast in 6–20 mm rods by a direct chill casting method and can be made into wire with the application of wire-feed additive manufacturing. We investigate the possibility of improving Al alloy SiC composite material properties by applying electromagnetic interactions during solidification. Electric current and a moderate static magnetic field (0.1–0.5 T) creates melt convection in mushy zone. Such interaction enhances heat and mass transfer near the solidification interface and hinders the re-agglomeration of the added particles.

In this study a technical solution is proposed to achieve an intense 50 Hz alternating magnetic field and a static magnetic field made by permanent magnet at the same place. A compact coil built by Bitter coil concept is customized to support alternating current, thus creating an alternating magnetic field. A complementary permanent magnet assembly is built around it to achieve the superposition of both fields along the axis of symmetry. Results from the experimental model are compared to both numerical and analytical models.