Dynamic Relaxation of Pd42.5Ni7.5Cu30P20 Metallic Glass

Amorphous physics and materials: Secondary relaxation and dynamic heterogeneity in metallic glasses: A brief review

“…[88] From the profile of the activation energy, the three discrete relaxation modes with various activation energies, i.e.,  relaxation (7.98 eV) is linked to the cooperative motion of ~5 atoms, slow  relaxation (1.39 eV) is associated with single atomic diffusion, and fast β' relaxation (0.25 eV) is mainly connected to rattling motion of atoms. It was demonstrated that the mechanical deformation behavior of metallic glasses depends on the various relaxation processes (i.e.…”

Volume and Enthalpy Relaxation in Pd_42.5Cu₃₀Ni_7.5P₂₀ Bulk Metallic Glass

“…These are reasonable values, although the pre-factor is a little too short. A similar analysis of the ¡-relaxation data 22) below T g resulted in unphysical values of 0¡ = 2.0 © 10 ¹69 s and E ¡ of 7.98 eV. These values reflect the fragile nature of this liquid, and indicate that the structure significantly changes with temperature so that activation energy is temperature dependent, 41) and the regular Arrhenian analysis is not applicable.…”

“…It is compared with the ¡-relaxation time 3,5,14,22) determined by the DMA measurement which is conventionally assigned to the structural relaxation in a liquid as a result of cooperative motion of atoms. The DMA relaxation time of supercooled liquid 3) (shown by blue squares) is consistent with the extrapolation of the DMA data in the glassy solid region 22) (blue circles). However, the structural relaxation time (black circles, diamonds and triangles) is significantly longer than the DMA relaxation time, particularly in the region close to T g .…”

“…However, if that is the case the amount of volume -annealed 2min 5min 10min 15min 20min 40min 70min 100min 200min 400min 700min 1000min 2000min 4000min 7000min 10000min T a =540 K Fig. 8 Relaxation times¸for static and dynamic relaxations are plotted against 1000/T, where dynamic data (blue symbols) include relaxation times measured in both supercooled liquid 3,5) (solid triangles and rectangles) and glassy solid regions 22) (solid circles). The black symbols denote static data, where the triangles represent static enthalpy data reported.…”

“…The evolution of different types of ¢-relaxation has been reported by DMA in a temperature range below T g . 5,22,23) For instance, they observed the ¢-relaxation events 23) related to hopping diffusion of P atom with a very short relaxation time of approximately 0.01 s at 512 K, about 60 K below T g .…”