|
|
[交流]
适用于纳米复合材料铝热剂燃烧反应的多级反应模式
|
Nanocomposite thermites include a reactive metal, in most cases aluminum, mixed on the nano-scale with a metal oxide. The nano-scale mixing achieved by ball-milling produces a highly developed and unusual interface area between reactive components. The high interface area assures a high reaction rate, attractive for propellants, explosives, and pyrotechnics. Development of a kinetic model for the initiation mechanisms of nanocomposite thermites prepared by arrested reactive milling (ARM) relies on differential scanning calorimetry (DSC) and thermal gravimetry (TG). These measurements identify and characterize multiple reaction steps important for ignition of these materials. However, for the ARM-prepared nanocomposites, interpretation of the DSC/TG data is challenging because of substantial but poorly resolved exothermic reactions occurring at low temperatures. These low temperature reactions are expected to contribute significantly to the processes that lead to ignition. Here, DSC and TG measurements were complemented by isothermal micro-calorimetry using TAM III resolving and quantifying these low temperature reactions. Based on the TAM III results, the accelerated oxidation in the ARM-prepared nano-thermites at low temperatures was attributed to Cabrera-Mott reaction, where the growth of very thin oxide layers is accelerated by electric field induced across such layers. This enabled a reaction mechanism for a 2Al∙3CuO nanocomposite powder prepared by ARM to be developed that included multiple oxidation steps starting with the CM reaction followed by direct oxidative growth of and phase changes in different alumina polymorphs. |
» 本帖附件资源列表
-
欢迎监督和反馈：小木虫仅提供交流平台，不对该内容负责。
本内容由用户自主发布，如果其内容涉及到知识产权问题，其责任在于用户本人，如对版权有异议，请联系邮箱：xiaomuchong@tal.com
- 附件 1 : 适用于纳米复合材料铝热剂燃烧反应的多级反应模式.pdf
2016-07-05 16:34:01, 444.44 K
» 猜你喜欢
|
回复此楼
修改论文，如何借助其他力量？
已经有4人回复
10