Non-isothermal crystallization transformation kinetics and isothermal crystallization kinetics in super-cooled liquid region（SLR） in Zr55Cu30Ni5Al10 bulk metallic glasses were studied by differential scanning calori...Non-isothermal crystallization transformation kinetics and isothermal crystallization kinetics in super-cooled liquid region（SLR） in Zr55Cu30Ni5Al10 bulk metallic glasses were studied by differential scanning calorimetry（DSC） and X-ray diffraction（XRD）.In isochronal mode,the average values of activation energy in Zr55Cu30Ni5Al10 bulk metallic glass determined by different models（Kissinger method,Flynn-Wall-Ozawa method and Augis-Bennett method） are in good agreement with each other.In addition,the isothermal transformation kinetics in Zr55Cu30Ni5Al10 bulk metallic glasses was described by the Johnson-Mehl-Avrami（JMA） model.For Zr55Cu30Ni5Al10 bulk metallic glass,the Avrami exponent n ranges from 2.2 to 2.9,indicating that crystallization mechanism in the bulk metallic glass was mainly diffusion-controlled;crystal growth is controlled by long range ordering diffusion in three-dimensional growth during isothermal crystallization process.The average value of activation energy in Zr55Cu30Ni5Al10 bulk metallic glass is 469 kJ/mol in isothermal transformation process.展开更多
文摘Non-isothermal crystallization transformation kinetics and isothermal crystallization kinetics in super-cooled liquid region（SLR） in Zr55Cu30Ni5Al10 bulk metallic glasses were studied by differential scanning calorimetry（DSC） and X-ray diffraction（XRD）.In isochronal mode,the average values of activation energy in Zr55Cu30Ni5Al10 bulk metallic glass determined by different models（Kissinger method,Flynn-Wall-Ozawa method and Augis-Bennett method） are in good agreement with each other.In addition,the isothermal transformation kinetics in Zr55Cu30Ni5Al10 bulk metallic glasses was described by the Johnson-Mehl-Avrami（JMA） model.For Zr55Cu30Ni5Al10 bulk metallic glass,the Avrami exponent n ranges from 2.2 to 2.9,indicating that crystallization mechanism in the bulk metallic glass was mainly diffusion-controlled;crystal growth is controlled by long range ordering diffusion in three-dimensional growth during isothermal crystallization process.The average value of activation energy in Zr55Cu30Ni5Al10 bulk metallic glass is 469 kJ/mol in isothermal transformation process.
