摘要
采用置换法通过对溶液浓度的控制实现了纳米Cu颗粒在微米Al粉表面定量、快速地化学沉积,制备出核一壳结构的Cu/Al微纳米复合粒子,并用SEM、EDS和XRD技术进行表征.在此基础上,利用DSC分析了Cu/ Al-WO_3的热反应性能,对比了Al-WO_3与Cu/Al-WO_3在不同化学配比下的热反应历程,同时分别提出了其相应的反应机理.实验结果表明,Cu/Al微纳米复合材料与WO_3的热反应活性明显高于传统微米级Al粉,并且在还原剂Cu/Al轻微过量时该热反应达到最佳效果.通过对Al粉表面改性,热反应的活化能降低了68.185 kJ·mol^(-1).
A kind of core-shell Cu/Al powder has been prepared via a facile displacement method, in which the micron-sized Al cores were coated in Cu shells. SEM, EDS and XRD were employed to characterize the samples. The thermal performance of micron-sized AI particles and Cu/Al micron-nano composites with WO3 were investigated by differential scanning calorimetry （DSC） as a function of the equivalence ratio. Mechanisms of thermite reactions have been proposed. Results indicated that the reactivity of Cu/Al micron-nano composites with WO3 was significantly higher than that of micron-sized Al particles, but depending strongly on equivalence ratio. The optimum equivalence was reached when the composites were fuel slightly rich. The activation energy of Cu/Al-WO3 was decreased by 68.185 kJ. mol^-1 compared with that of Al-WO3.
出处
《物理化学学报》
SCIE
CAS
CSCD
北大核心
2007年第11期1753-1759,共7页
Acta Physico-Chimica Sinica
基金
国家自然科学基金(50602024)
总装备部预研项目(41328030507)资助
