Reactive mechanical alloying

Milling atmosphere, which is a neutral protective gas (helium or argon) during mechanical milling or hydrogen under pressure up to 0.9 MPa under reactive mechanical alloying processes. 

In a variant of the second method described earlier the premixed metallic powders (or pulverized ingots) are milled under hydrogen atmosphere to directly form an intermetallic hydride. It can be also viewed as hydrogen alloying of metal powders and powder mixtures in hydrogen alloying mills. This method is called a reactive mechanical alloying (RMA) or mechanochemical synthesis (MCS). 

Much more efficient method of the synthesis of metal hydrides is a one-step method of reactive ball milling of elemental metal directly under hydrogen gas. The method of reactive mechanical alloying/milling of either elemental metals or preaUoyed... 

Fig. 3.1 XRD patterns of 2Mg-Fe powders reactively mechanically alloyed under low-energy...

The most exhaustive studies of the synthesis and hydrogen storage properties of Mg CoHj synthesized by RMA (reactive mechanical alloying) and a combination of RMA and sintering were carried out by the group led by Gennari [63-65]. They observed a transition from tetragonal to cubic structure of Mg CoH at... 

F.C. Gennaii, F.J. Castro, J.J. Andrade Gamboa, Synthesis of Mg FeH by reactive mechanical alloying formation and decomposition properties , J. Alloys Compd 339 (2002) 261-267. 

R.A. Vaiin, S. Li, A. Calka, D. Wexler, Formation and environmental stability of nanocrystalline and amorphous hydrides in the 2Mg-Fe mixture processed by controlled reactive mechanical alloying (CRMA) , J. Alloys Compd. 313 (2004) 270-286. 

F.C. Gennari, F.J. Castro, G. Urretavizcaya, Hydrogen desorption behavior from magnesium hydrides synthesized by reactive mechanical alloying, J. Alloys Compd. 321 (2001) 46-53. 

Key words hydrogen storage/nanostructured light metal-based hydrides/controlled reactive mechanical alloying/magnesium hydride/amorphous hydrides... 

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