Substitutional alloy of Ce and Al

• The formation of substitutional alloys has been restricted to elements with similar atomic radii and electronegativity. Using high-pressure at 298 K, we synthesized a face-centered cubic disordered alloy of highly dissimilar elements (large Ce and small Al atoms) by compressing the Ce3Al intermetallic compound > 15 GPa or the Ce3Al metallic glass > 25 GPa. Synchrotron X-ray diffraction, Ce L-3-edge absorption spectroscopy, and ab initio calculations revealed that the pressure-induced Kondo volume collapse and 4f electron delocalization of Ce reduced the differences between Ce and Al and brought them within the Hume-Rothery (HR) limit for substitutional alloying. The alloy remained after complete release of pressure, which was also accompanied by the transformation of Ce back to its ambient 4f electron localized state and reversal of the Kondo volume collapse, resulting in a non-HR alloy at ambient conditions.

Keyword

4f electron delocalization

Ce-Al solid solution alloy

high pressure

Hume-Rothery rules

metallic glass

high-pressure

metallic glasses

crystal-structure

room-temperature

alpha transition

cerium metal

behavior

approximation

potassium

chemistry

TECHNOLOGY

TEKNIKVETENSKAP

Publication and Content Type

ref (subject category)

art (subject category)