Microstructural characteristics and wear resistance of electromagnetic casting aluminum alloys

Direct chill casting (DCC) has some demerits such as oscillation and subsurface segregation. Electromagnetic casting (EMC) technology was used to solve these problems. The electromagnetic force prevented the metal from touching the mold, which contributes to leaving the ingot surface very smooth. Moreover, the electromagnetic stirring and joule heating made the structure become more homogeneous over the entire cross-section. It results in the EMC ingots having distinct merits. Tbe 2024 and 5182 Al alloys were made using EMC and DCC technology. Parts of them were used for specimens. OM and SEM were carried out to analyze the microstructures. Hardness and wear resistance tests were carried out in order to investigate mechanical properties. On the other hand, the solution and aging treatment effects on mechanical charaterization were compared between EMC and DCC ingots. Micrographs show that EMC ingots have a very fine and uniform grain structure, which makes the EMC ingots have high strength and good ductility. The EMC specimens have twice the hardness of DCC specimens in the as-east state. They also express excellent wear resistance characteristics.