针对典型的U₆₀Fe_27.5Al_12.5非晶合金,利用差示扫描量热仪进行了非等温晶化与等温晶化过程的动力学研究,并采用不同的理论方法进行了数据分析。发现该合金的玻璃化转变激活能略高于270 kJ/mol,熔体脆度接近22,证实了其属于强金属玻璃体系材料。基于第一放热晶化峰,由非等温晶化方法得到其晶化激活能位于205~275 kJ/mol范围,而由等温晶化方法得到的结果位于280~390 kJ/mol区间,前者明显低于后者,与一般的非晶合金表现一致,其原因是前一种方法的测试过程中温度不断升高,更易于激发晶化反应。前一种方法获得的动力学因子大都位于3~4之间,略高于后一种方法得到的动力学因子主体区间2.5~3,这既证明该非晶的晶化以形核为主,也说明升温过程更易于促使形核发生。

Due to their high strength and excellent anticorrosive properties, U-based amorphous alloys are quite promising for applications in nuclear-related fields. However, they face the challenge of crystallization due to high temperatures during some applications. Currently, focus on the crystallization mechanism of such materials is limited; thus, further investigation is required. Herein, using differential scanning calorimetry, both nonisothermal and isothermal crystallization kinetics of typical amorphous U₆₀Fe_27.5Al_12.5 alloy were investigated. This alloy was further analyzed using different theoretical methods. The alloy exhibited the glass transition activation energy of slightly more than 270 kJ/mol and the melt fragility value of about 22, indicating that it is a strong metallic glass material. Based on the first exothermal crystallization peak, this glassy alloy is believed to possess the crystallization activation energy of 205-275 kJ/mol within nonisothermal method and 280-390 kJ/mol within the other method. The former value is much lower than the latter, which is consistent with the results of the conventional amorphous alloys. This general trend is mainly because crystallization can be activated more easily by a continuous increase in temperature. The kinetic factor of the alloy was in the ranges of 3-4 and 2.5-3 under the nonisothermal and isothermal conditions, respectively, demonstrating that the devitrification of the noncrystalline U-Fe-Al alloy greatly depends on the nucleation process, which is prone to occur during a rise in temperature.