Al-Ni-RE非晶合金的晶化行为和热稳定性

本文制备了一系列Al-Ni-RE (RE=La, Ce, Y) 非晶合金薄带, 利用差示量热扫描仪和X射线衍射仪考察了非晶合金的晶化行为和初生相, 并分析了其与合金成分和原子特性间的关系. 结果表明: 在拓扑不稳定参数λ以有效原子半径修正为λ'后, 每一Al-Ni-RE非晶合金体系可由其两个临界值划分为纳米晶、纳米玻璃和玻璃三类; Al-Ni-RE非晶合金的晶化开始温度和混合焓与λ'成良好的线性关系, 即λ'能很好的表征Al基非晶合金的热稳定性. 关键词： Al基非晶 玻璃转变 初生相 热稳定性

Crystallization behavior and thermal stability of Al-Ni-RE metallic glasses

A series of Al-Ni-RE (RE=La, Ce, Y) amorphous ribbons were prepared. The crystallization behavior and primary phases were investigated using X-ray diffraction and differential scanning calorimeter, and their relationships with the alloy composition and atomic features were analyzed. Results show that if the topological instability parameter λ was modified using effective atomic radii, the metallic glasses in an Al-Ni-RE system can be classified into nanocrystalline, nanoglassy and glassy types according to their crystallization behaviors by two critical values of the modified topological instability parameter λ'. Linear relationships of onset temperature of crystallization and mixing enthalpy with λ' are also clearly revealed, indicating that λ' is closely related to the thermal stability of Al-Ni-RE metallic glasses.
Keywords： Al-based metallic glass glass transition primary phase thermal stability