arXiv subjects

J. B. Cui

Publications and source records attributed to J. B. Cui.

3 recordsLinked to original sources

arXiv2025

Relationship of structural disorder and stability of supercooled liquid state with glass-forming ability of metallic glasses

We performed calorimetric studies of 26 metallic glasses and calculated the excess entropy and excess enthalpy with respect to their counterpart crystals. On this basis, we introduced a dimensionless entropy-based parameter {\sigma}scl, which characterizes structural disordering and stability of the supercooled liquid state upon heating. A very good correlation of {\sigma}scl with literature data on the critical cooling rate Rc and critical diameter Dmax of metallic glasses is shown. We also introduced another dimensionless parameter {\eta}scl based on the excess enthalpy of glass and showed that {\eta}scl provides equally good correlation with Rc and Dmax. Possible relationship of structural disordering and glass-forming ability in the supercooled liquid range with the defect structure of glass is discussed. The obtained results provide a new window for the understandingof the glass-forming ability of metallic glasses.

cond-mat.dis-nn↗

arXiv2025

Non-isothermal stress relaxation in conventional and high-entropy metallic glasses and its relationship to themixing and excess entropy

We performed calorimetric and torsion stress relaxation measurements upon linear heating of six conventional and high-entropy metallic glasses with the mixing entropy {\Delta}Smix ranging from 0.86R to 1.79R (R is the universal gas constant). It is shown that high-entropy metallic glasses ({\Delta}Smix > 1.5 R) exhibit significantly greater resistance to stress relaxation. Based on calorimetric data, we calculated the excess entropy of glass relative to the counterpart crystalline state and introduced an entropy-based dimensionless parameter {\Delta}S, which characterizes the rise of the entropy and structural disordering of glass in the supercooled liquid region. It is shown that the depth of stress relaxation at a given temperature decreases with {\Delta}Smix but increases with {\Delta}S. Possible reasons for this relationship are discussed.

cond-mat.dis-nn↗

arXiv2023

Effect of the entropy on the shear viscosity of metallic glasses near the glass transition

We measured the shear viscosity of 14 metallic glasses differing with their mixing entropy $ΔS_{mix}$. It is found that the viscosity at the glass transition temperature $T_g$ significantly increases with $ΔS_{mix}$. Using calorimetric data, we calculated the excess entropy of all glasses $ΔS$ with respect to their maternal crystalline states as a function of temperature. It is shown that the excess entropy $ΔS$ both at room temperature and at $T_g$ \textit{decreases} with $ΔS_{mix}$. It is concluded that glasses with "high mixing entropy" $ΔS_{mix}$ correspond to MGs with \textit{low} excess entropy $ΔS$. The origin of the increased shear viscosity at $T_g$ of glasses with high $ΔS_{mix}$ is determined by their reduced excess entropy $ΔS$.

cond-mat.dis-nn↗