Al_(85)Ni_(10)Er_5非晶合金晶化动力学效应的研究

Preparation and Kinetics of Crystallization of Al_(85)Ni_(10)Er_5 Amorphous Alloy

应用Kissinger公式计算得到Al_(85)Ni_(10)Er_5非晶合金初始晶化激活能Ex为104 k J/mol.计算了Al_(85)Ni_(10)Er_5非晶合金的拓扑不稳定参数λ=0.087,说明合金是铝基纳米晶合金.Al_(85)Ni_(10)Er_5非晶合金第一放热峰的晶化体积分数与温度的关系曲线均呈"S"形,随升温速率的增加,这种"S"形曲线均向高温处移动.合金晶化第一阶段的晶化激活能Ea(x)与晶化体积分数呈线性递减趋势.此外,晶化体积分数在10%~50%阶段的激活能Ea(x)大于合金初始晶化激活能Ex,这是由于非晶合金内稳定的无序原子团簇结构有效地抑制了初生晶相长大的结果.

Al85Ni10Er5 amorphous alloys were prepared by melt-spinning method. Preparation and kinetics of crystallization of Al85Ni10Er5 alloy were studied by the differential scanning calorimetry （ DSC ）, and the first primary crystallization activation energy （Ex） of Al85Ni10Er5 amorphous alloys was obtained as 104 kJ/mol. The topological instability parameter k of Al85Ni10Er5 amorphous alloy was calculated as 0. 087, indicating that Al85Ni10Er5 alloy is nanocrystalline alloy. The curves of relation of crystallized fraction with temperature at different heating rates exhibited as a function of ＂S＂ shape. A linear relationship was observed, which values of crystallization activation energy Eo （x） decreased with crystallized fraction x increased. In addition, crystallization activation energy Ea （x） is greater than the primary crystallization activation energy （Ex） in the crystallized volume fraction from 10% to 50%. The results indicated that further growth of primary crystalline phase was effectively hindered by the disordered atom cluster structure in Al85Ni10Er5 amorphous alloy.