快淬Nd--Fe--B非晶厚带的晶化过程和非等温晶化动力学

金属学报, 2009, 45(2): 237-242.

快淬Nd--Fe--B非晶厚带的晶化过程和非等温晶化动力学

王大鹏包小倩张茂才朱洁

(北京科技大学新金属材料国家重点实验室

State Key Laboratory of Advanced Metals and Materials

University of Science and Technology Beijing

Beijing 100083

关键词： Nd--Fe--B , amorphous alloy , crystallization kinetics , crystallization activationt energy

CRYSTALLIZATION PROCESS AND NON–ISOTHERMAL CRYSTALLIZATION KINETICS OF MELT–SPUN Nd–Fe–B AMORPHOUS THICK RIBBONS

WANG Dapeng

Keywords： Nd–Fe–B , 非晶 , 晶化动力学 , 晶化激活能

利用熔体快淬法在12 m/s的辊速下制备了Nd₆Fe₇₂B₂₂和Nd₆Fe₆₈Ti₄B₁₇C₅非晶厚带. 通过DSC和XRD, 并借助Kempen模型和 Kissinger方程, 研究了合金的非晶晶化过程及非等温晶化动力学. 结果表明, 两种合金厚带具有不同的晶化过程以及晶化动力学机制. Nd₆Fe₇₂B₂₂合金的晶化过程分为三步完成: 非晶
相 (AP)→ Nd₂Fe₂₃B₃→Nd₂Fe₁₄B+ α--Fe +Fe₃B→Nd₂Fe₁₄B+α--Fe+Fe₃B+NdFe₄B₄, 而Nd₆Fe₆₈Ti₄B₁₇C₅ 合金一步完成晶化: AP→Nd₂(Fe, Ti)₁₄(B, C)+α--Fe + Fe₃B. 与Nd₆Fe₇₂B₂₂合金由界面控制的多晶型晶化不同, Nd₆Fe₆₈Ti₄B₁₇C₅合金以扩散控制的共晶型晶化为主.

Crystallization processes and non–isothermal crystallization kinetics of Nd₆Fe₇₂B₂₂and Nd₆Fe₆₈Ti₄B₁₇C₅ amorphous thick ribbons rapidly quenched at a roller running rate of 12 m/s were investigated by means of DSC, XRD, Kempen model and Kissinger equation, respectively.
Two thick ribbons show different crystallization processes and kinetic mechanisms. The crystallization processes of Nd₆Fe₇₂B₂₂ and Nd₆Fe₆₈Ti₄B₁₇C₅alloys can be discribed as: amorphous phase (AP)→ Nd₂Fe₂₃B₃→Nd₂Fe₁₄B+ α--Fe +Fe₃B→Nd₂Fe₁₄B+α--Fe+Fe₃B+NdFe₄B₄, and AP→Nd₂(Fe, Ti)₁₄(B, C)+α--Fe + Fe₃B, respectively. Different from polymorphic crystallization controlled by interface for Nd₆Fe₇₂B₂₂ alloy, the crystallization of Nd₆Fe₆₈Ti₄B₁₇C₅ is eutectoidic and the nucleus growth is controlled by diffusion.

参考文献

[1]
[2]
[3]
[4]
[5]
[6]
[7]
[8]
[9]
[10]
[11]
[12]
[13]
[14]
[15]
[16]
[17]
[18]
[19]

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