Rheology and ultrasonic properties of Pt57.5Ni5.3Cu14.7P22.5 liquid

The equilibrium and nonequilibrium viscosity and isoconfigurational shear modulus of Pt57.5Ni5.3Cu14.7P22.5 supercooled liquid are evaluated using continuous–strain-rate compression experiments and ultrasonic measurements. By means of a thermodynamically-consistent cooperative shear model, variations in viscosity with both temperature and strain rate are uniquely correlated to the variations in isoconfigurational shear modulus, which leads to an accurate prediction of the liquid fragility and to a good description of the liquid strain-rate sensitivity

Anelastic to Plastic Transition in Metallic Glass-Forming Liquids

The configurational properties associated with the transition from anelasticity to plasticity in a transiently deforming metallic glass-forming liquid are studied. The data reveal that the underlying transition kinetics for flow can be separated into reversible and irreversible configurational hopping across the liquid energy landscape, identified with beta and alpha relaxation processes, respectively. A critical stress characterizing the transition is recognized as an effective Eshelby “backstress,” revealing a link between the apparent anelasticity and the “confinement stress” of the elastic matrix surrounding the plastic core of a shear transformation zone

Deformation of glass forming metallic liquids: Configurational changes and their relation to elastic softening

The change in the configurational enthalpy of metallic glass forming liquids induced by mechanical deformation and its effect on elastic softening is assessed. The acoustically measured shear modulus is found to decrease with increasing configurational enthalpy by a dependence similar to one obtained by softening via thermal annealing. This establishes that elastic softening is governed by a unique functional relationship between shear modulus and configurational enthalpy

The edge-to-vertex Steiner domination number of a graph

A set W ⊆ E is said to be an edge-to-vertex Steiner dominating set of G if W is both an edge-to-vertex dominating set and a edge-to-vertex Steiner set of G. The edge-to-vertex Steiner domination number γsev(G) of G is the minimum cardinality of its edge-to-vertex Steiner dominating set of G and any edge-to-vertex Steiner dominating set of cardinality γsev(G) is a γsev-set of G. Some general properties satisfied by this concept are studied. The edge-to-vertex Steiner domination number of certain classes of graphs are determined. Connected graph of size q ≥ 3 with edge-to-vertex Steiner domination number q or q −1 are characterized. It is shown for every pair a, b of integers with 2 ≤ a ≤ b, there exists a connected graph G such that γev(G) = a and γsev(G) = b.Emerging Sources Citation Index (ESCI)MathScinetScopu

Stochastic Metallic-Glass Cellular Structures Exhibiting Benchmark Strength

By identifying the key characteristic “structural scales” that dictate the resistance of a porous metallic glass against buckling and fracture, stochastic highly porous metallic-glass structures are designed capable of yielding plastically and inheriting the high plastic yield strength of the amorphous metal. The strengths attainable by the present foams appear to equal or exceed those by highly engineered metal foams such as Ti-6Al-4V or ferrous-metal foams at comparable levels of porosity, placing the present metallic-glass foams among the strongest foams known to date