Naslov
The effect of high energy ball milling on the crystal structure of GdNi5

Autori
Stubičar, Mirko ; Blažina, Želimir ; Tonejc, Antun ; Stubičar, Nada ; Krumes, Dragomir

Izvornik
Physica B: Condensed Matter (0921-4526) 304 (2001), 1/4; 304-308

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
x-ray powder diffraction; high energy ball milling; GdNi5 intermetallic compound

Sažetak
X-ray powder diffraction was used to determine the effect, of dry, in air performed high energy ball milling, on the intermetallic compound GdNi5. It was found that the crystal structure of GdNi5 is not stable, and at the early stage of milling (up to after 10 h of milling) it decomposes into the constituent metals gadolinium and nickel, whereby gadolinium at once oxidises into monoclinic Gd2O3. Both, the crystallite (grain) size and the particle size of powder decrease during the early stage of milling. At the later stage of milling (up to 50 h) the nickel phase from the mixture of Gd2O3 and nanocrystalline nickel oxidises into nanocrystalline NiO. Therefore, the final product after 150 h of milling of GdNi5 is a mixture of oxides of the constituent metals, i.e., amorphous Gd2O3 and nanocrystalline NiO. Traces of contamination by a-SiO2 have been observed in the milled powder, being more pronounced as the milling process proceeds. This is ascribed to the wear effect of agate milling assembly.

Izvorni jezik
Engleski

Znanstvena područja
Fizika, Kemija, Strojarstvo

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