| Abstract Scope |
Rare earth elements have gained a lot of attention in aluminum alloys. The addition of ppm levels of these elements such Er, Eu, Sm, Ce modifies the microstructure efficiently and thereby enhanced mechanical properties can be achieved. There are several publications in the literature claiming that addition of these elements yields to pore formation and thus, instead of benefits in mechanical properties, the cast parts suffer from porosity. In this work, a systematic experimental study was carried where the master alloys of Er, Eu, Sm, Ce was melted, and reduced pressure test samples were collected. Then, these alloys were added to A356 and melt cleanliness, microstructure and tensile properties were investigated. It was found that most of the porosity in the modified castings was based on the oxide content of the master alloys. |