玻璃转变及晶化的影响
( 华中科技大学 材料科学与技术系， 武汉 430074)
摘 要: 采用示差扫描量热（DSC）分析方法， 测定了大块非晶合金Pd-40Cu-30Ni-10P-20经523K（（T-g-100K）<T<T-g）不同时间（0~64h）预退火后的玻璃转变温度T-g、 玻璃转变峰温度/T/-M、 起始晶化温度T-x、 晶化峰的峰温T-p、 晶化焓以及在玻璃转变过程中的比热容增量， 并根据Kissinger公式计算了晶化的表观活化能。同时， 测量了不同时间预退火后样品的显微硬度。 结果表明： 在玻璃转变温度以下的预退火处理使Pd-40Cu-30Ni-10P-20大块非晶合金的微观原子组态发生变化，从而影响了其随后的玻璃转变行为， 但对晶化的影响不大。 其显微硬度随预退火时间的延长而逐步增加后趋于稳定。 并利用结构弛豫理论分析了预退火对玻璃转变、 晶化和显微硬度的影响。
关键字: 大块非晶合金; 结构弛豫; 玻璃转变; 晶化
crystallization of Pd-40Cu-30Ni-10P-20
（ Department of Materials Science and Technology,
Huazhong University of Science and Technology, Wuhan 430074, China）
Abstract: Differential scanning calorimeter(DSC) was used to investigate the specific heat difference, glass transition temperature, onset crystallization temperature, and their corresponding peak temperature, respectively, around glass transition region and crystallization enthalpy for Pd-40Cu-30Ni-10P-20 bulk amorphous alloys pre-annealed at 523K for different times (0-64 h). The apparent activation energies for crystallization were calculated by Kissinger equation. The micro-hardness of pre-annealed amorphous state was also measured. It is found that the glass transition behavior of Pd-40Cu-30Ni-10P-20 bulk amorphous alloy is influenced significantly due to atomic coorperation re-arrangement as a result of pre-annealing below glass transition temperature. The crystallization, however, seems to have no relation to pre-annealing time when pre-annealing temperature is 523K. In addition, the micro-hardness tends to level off after a steady rise with increasing of pre-annealing time. The effects of pre-annealing time on glass transition, crystallization and micro-hardness of Pd-40Cu-30Ni-10P-20 bulk amorphous alloy were discussed in terms of theory of structural relaxation.
Key words: bulk amorphous alloy; structural relaxation; glass transition; crystallization
