Casting Fe–Al-based intermetallics alloyed with Li and Ag

摘要

The effect on the mechanical properties at room temperature of Li and Ag additions to the Fe–Al (40 at.%)-based alloy produced by conventional casting were evaluated in this work. Alloying elements were added into a previously molted Fe–(40 at.%) aluminum-based alloy, stirred, and then cast into sand molds to directly produce tensile specimens. To determine the udmechanical properties, tensile tests and hardness measurements were performed. The additions of both Ag and Li showed an increase in ductility and tensile strength of the intermetallic alloys.udIn addition, hardness was substantially increased with the Li addition. Lithium additions promoted a solid solution hardening, whereas 3 at.% of Ag additions promoted ductility due to a microstructural modification and to the formation of a soft Ag 3 Al phase. Characterization by both optical and electronic microscopy, energy dispersive spectroscopy microanalysis, and x-ray diffraction supported the mechanical characterization.