Energy-releasing and phase transitions of Ti-based bulk metallic glass composites during heating

The energy-releasing and phase transitions of Ti-based bulk metallic glass composites (BMGCs) during heating largely remain elusive. Here, the effects of cooling rates and compositional changes on energy-releasing and phase transitions of two BMGCs containing relatively stable 8 -Ti crystals or metastable 8 -Ti crystals are inves-tigated. With decreasing the cooling rates, both BMGCs transform from non-equilibrium BMGCs to quasi -equilibrium BMGCs. Moreover, decreasing the Co content reduces the phase stability of 8 -Ti. DSC heating, isothermal to-Ti precipitates in 8 -Ti crystals before Tg, and as the temperature above Tx, the glass matrix un-dergoes crystallization. With decreasing the cooling rates, both the relaxation and crystallization enthalpies decrease, but which can be significantly enhanced by decreasing the Co content, suggesting that BMGCs with unstable 8 -Ti dendrites are of better energy-releasing properties. These findings not only reveal the energy changes and phase transitions of BMGCs during heating, but also promote their practical applications as energy -releasing materials.