INVESTIGADORES
ESQUIVEL Marcelo Ricardo Oscar
artículos
Título:
A comparison of the evolution during the mechanical alloying of both a MmNi5Ni and a MmNi mixtures: Stages of milling and microstructural characterization
Autor/es:
M.R ESQUIVEL.; G. MEYER
Revista:
JOURNAL OF ALLOYS AND COMPOUNDS
Editorial:
ELSEVIER
Referencias:
Lugar: AMSTERDAMM; Año: 2007 vol. 446 p. 212 - 217
ISSN:
0925-8388
Resumen:
The advantages attributed to hydride forming materials synthesized by either mechanical alloying (MA) or milling (MM) are related to an enhancement of the alloy conditioning previous to sorption of hydrogen, mainly due to the generation of defects and strain on the microstructure. This treatment can be done either after the synthesis by further MM of the alloy or simultaneously by MA of the constituents. To select the most suitable method, mixtures of MmNi and MmNi5Ni were mechanically alloyed/milled in a low energy milling device. The changing of the microstructure during processing was analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The evolution of particle morphology and size were analyzed and the stages of alloying/milling were identified. The MA process of the MmNi mixture occurs in four stages: initial, intermediate, final and completion. The MM process of the MmNi5Ni mixture occurs in two main stages, governed successively by fracture and cold welding, respectively. The final alloy condition, structure and microstructure are correlated to the evolution of each process.