Mechanical Alloying Processes and Reactive Milling (Overview)
Mechanical Alloying Processes and Reactive Milling (Overview)
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机械合金化工艺和反应铣削（概述）
DOI：
10.2320/matertrans1989.36.150
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发表时间：
1995
期刊：
影响因子：
--
通讯作者：
L. Schiffini
中科院分区：
文献类型：
--
作者：
G. Cocco;G. Mulas;L. Schiffini
机械驱动过程在功能材料设计中的巨大灵活性已经引起了不同分支和研究领域的广泛关注。我们目前的兴趣关注的是非晶态金属粉末的固有化学性质-鉴于在多相催化中的可能开发-以及它们在反应研磨下的化学行为。化学效应被认为是负责改变过程中的机械合金化过程（MA）。此外，在研磨下的粉末的深层结构表征揭示了来自反应环境的气体污染物的微妙的，有时是不可避免的影响。这些结果是利用互补衍射技术，特别是中子衍射分析得到的。在反应研磨和机械化学方面提到这些化学方面是很自然的。在此框架内，我们专注于氢的积极作用，作为气体试剂或以活化形式从金属氢化物晶格中释放，以引导MA和机械研磨（MM）过程的最终产品。在此基础上，还证明了在研磨下进行气相氢化反应的可能性。为了更好地理解潜在的机制，MA和机械化学都需要正确定义主要的铣削参数。为此，简要概述了直接评价球磨过程中的碰撞频率和能量因素的实验方法。
The great flexibility of mechanically driven processes in designing functional materials has stimulated wide attention in the different side branches and research fields. Our current interest concerns both the inherent chemical properties of amorphous metal powders-in view of a possible exploitation in heterogeneous catalysis-as well as their chemical behaviors under reactive milling. Chemical effects were found to be responsible for changing the course of Mechanical Alloying processes (MA). Furthermore, deep structural characterizations of the powders under milling have revealed the subtle and sometimes unavoidable influence of gaseous contaminants from the reaction environment. These results were obtained from the use of complementary diffraction techniques and from the neutron diffraction analysis in particular. It is only natural to refer to these chemical aspects in terms of reactive milling and Mechanochemistry. Within this framework we focused on the active role of hydrogen, as a gaseous reagent or released in activated form from metal hydride lattices, to steer the end-products of MA and Mechanical Milling (MM) processes. On this basis, the possibility to run gaseous hydrogenation reactions under milling was also proven. For a better understanding of the underlying mechanism, MA and Mechanochemistry both require the proper definition of the main milling parameters. To this extent, an experimental method is briefly outlined for the direct evaluation of the collision frequency and energetical factors in ball milling processes.