Gibbs free energy difference between the undercooled liquid and the beta-phase of a Ti-Cr alloy

The heat of fusion and the specific heats of the solid and liquid have been experimentally determined for a Ti60Cr40 alloy. The data are used to evaluate the Gibbs free energy difference, DELTA-G, between the liquid and the beta-phase as a function of temperature to verify a reported spontaneous vitrification (SV) of the beta-phase in Ti-Cr alloys. The results show that SV of an undistorted beta-phase in the Ti60Cr40 alloy at 873 K is not feasible because DELTA-G is positive at the temperature. However, DELTA-G may become negative with additional excess free energy to the beta-phase in the form of defects

Gibbs free-energy difference between the glass and crystalline phases of a Ni-Zr alloy

The heats of eutectic melting and devitrification, and the specific heats of the crystalline, glass, and liquid phases have been measured for a Ni24Zr76 alloy. The data are used to calculate the Gibbs free-energy difference, DeltaGAC, between the real glass and the crystal on an assumption that the liquid-glass transition is second order. The result shows that DeltaGAC continuously increases as the temperature decreases in contrast to the ideal glass case where DeltaGAC is assumed to be independent of temperature