Mg segregation at coherent and semi-coherent Al/Al3Sc interfaces
نویسندگان
چکیده
Aluminum alloys containing Sc are promising materials for high-temperature structural applications due to the high strengthening effect of the Al3Sc (L12 structure) precipitates [1]. Further improvements in strength and nanostructural stability of Al-Sc based alloys are achieved by adding alloying elements, such as Mg, as solid-solution strengtheners. It is important to understand the effects of Mg in order to control not only the specific contribution of Mg to the properties of Al-Sc alloys (strengthening effect and creep resistance) but also the changes in the nanostructure. From previous work, it is known that Mg tends to segregate to the coherent Al/Al3Sc interface due to positive interactions between Mg and Sc atoms [2]. This paper reports measurements of Mg segregation at the Al/Al3Sc interface and compares the segregation level between coherent and semicoherent Al/Al3Sc interfaces.
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