Microstructural characteristics and wear resistance of electromagnetic casting aluminum alloys

Direct chill casting (DCC) has some demerits such as oscillation and subsur face segregation. Electromagnetic casting (EMC) technology was used to solv e these problems. The electromagnetic force prevented the metal from touchi ng the mold, which contributes to leaving the ingot surface very smooth. Mo reover, the electromagnetic stirring and joule heating made the structure b ecome 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 resistan ce tests were carried out in order to investigate mechanical properties. On the other hand, the solution and aging treatment effects on mechanical cha raterization were compared between EMC and DCC ingots. Micrographs show tha t 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 tw ice the hardness of DCC specimens in the as-east state. They also express e xcellent wear resistance characteristics.