Amorphous solid

Catalysis

Metallurgy

Materials science

Social psychology

Differential scanning calorimetry

Transition metal

Biochemistry

Computer science

Polymer

Thermodynamics

Physics

Amorphous metal

Alloy

Psychology

Merge (version control)

Glass transition

Calorimetry

Relaxation (psychology)

Condensed matter physics

Composite material

Crystallography

Information retrieval

Chemistry

National Science Review

One puzzling phenomenon in glass physics is the so-called ‘shadow glass transition’ which is an anomalous heat-absorbing process below the real glass transition and influences glass properties. However, it has yet to be entirely characterized, let alone fundamentally understood. Conventional calorimetry detects it in limited heating rates. Here, with the chip-based fast scanning calorimetry, we study the dynamics of the shadow glass transition over four orders of magnitude in heating rates for 24 different hyper-quenched metallic glasses. We present evidence that the shadow glass transition correlates with the secondary (β) relaxation: (i) The shadow glass transition and the β relaxation follow the same temperature–time dependence, and both merge with the primary relaxation at high temperature. (ii) The shadow glass transition is more obvious in glasses with pronounced β relaxation, and vice versa; their magnitudes are proportional to each other. Our findings suggest that the shadow glass transition signals the thermodynamics of β relaxation in hyper-quenched metallic glasses.

Shadow glass transition as a thermodynamic signature of β relaxation in hyper-quenched metallic glasses