Nanocrystallization of Zr-Ti-Cu-Ni-Be bulk meiallic glass

作者：Gao YL^*; Shen J; Sun JF; Chen DM; Wang G; Wang HR; Xing DW; Xian HZ; Zhou BD

来源：Materials Letters, 2003, 57(16-17): 2341-2347.

DOI：10.1016/S0167-577X(02)01222-3

• bulk metallic glass
• nanocrystallizationl
• kissinger equation
• activation energy
• crystallization products

The nanocrystallization kinetics Of Zr41.2Ti13.8Cu12.5Ni10Be22.5 (at.%) bulk metallic glass was investigated by differential scanning calorimetry (DSC) in the mode of continuous heating and isothermal annealing. In the case of continuous heating, three exothermic crystallization peaks can be observed, and the. peak temperatures display a strong dependence on the heating rates, which can be fitted by a first order. decay equation. The activation energies for crystallization are estimated to be E-p1 = 166.83 +/- 8.85 kJ/mol, E-p2 = 256.15 +/- 9.34 kJ/mol, E-p3 = 174.36 +/- 12.56 kJ/mol, which correspond to peak temperatures Of T-p1, T-p2, and T-p3, respectively, indicating the formation of different crystallization phases at different stages. In the case of isothermal annealing, the crystallization products under isothermal annealing were observed and determined by transmission electron microscopy (TEM). The precipitation phases of the sample heated at higher temperatures were identified by X-ray diffraction (XRD), showing that the body-centered tetragonal (bct) Zr2Cu and hexagonal ZrBe2 are the primary phases, in spite of the presence of other phases. These results are consistent with the complexity of the DSC curves obtained during the continuous heating and isothermal annealing.

• 出版日期2003-5
• 单位哈尔滨工程大学; 哈尔滨工业大学; 山东大学