Revista de Engenharia Civil e Ambiental

A Scandium Modified Al-0.7 Fe Binary Alloy: Improvement of Creep- Resistance Property

Abstract

Jiayi Zhang ,Xinyang Jiang ,Mingyang Ma ,Bin Wang *,Danqing Yi ,Bo Jiang

The creep behaviors and microstructures of Al-0.7Fe and Al-0.7Fe-0.2Sc alloy are investigated through creep tests, optical microscope, electron probe micro-analyze and transmission electron microscope observations. It is found that the steady state creep rates of Al-0.7Fe-0.2Sc are smaller than that of Al-0.7Fe under different temperatures at 70 Mpa. An overview of microstructure is given, the interactions between intermetallic phases and dislocations are investigated, with an emphasis on the Al3Sc precipitates. The mechanism controlling creep-resistance is explained by Orowan strengthening mechanism. The magnitude of Δσ Or can afford dislocations to bypass Al3Sc precipitates in Al-0.7Fe-0.2Sc alloy. The counter flow of the vacancies and solute atoms are induced to expound the dislocation motion mechanism.