Main α relaxation and slow β relaxation processes in a La ₃₀ Ce ₃₀ Al ₁₅ Co ₂₅ metallic glass

Dynamic relaxation processes are fundamental to understand the mechanical and physical properties of metallic glasses. In the current work, mechanical relaxations in a La ₃₀ Ce ₃₀ Al ₁₅ Co ₂₅ bulk metallic glass were probed by dynamic mechanical analysis. In contrast to many metallic glasses, La ₃₀ Ce ₃₀ Al ₁₅ Co ₂₅ metallic glass shows a pronounced slow β relaxation peak. Physical aging below the glass transition temperature T _g leads to an increase of the apparent activation energy and a decrease of the slow β relaxation magnitude. The correlation between the slow β relaxation and the main α relaxation is discussed.