Properties improvement of the al 7075 alloy castings

The microstructure and the mechanical properties of the samples obtained by conventional vertical continuous casting and electromagnetic casting of 7075 aluminum as-cast alloy were investigated. The better surface quality, more homogeneous alloying elements distribution and hence the microstructure and better mechanical properties were obtained in samples casted with electromagnetic field (EMF) compared with samples casted without EMF. The microstructure was analyzed by optical microscope and the variation of alloying elements, Zn and Mg, through the sample cross section was examined by chemical analysis. The mechanical properties of samples casted with and without electromagnetic field were determined using computerized materials testing machine Zwick/Roel Z 100.