On the Phase Transformation in Mechanically Alloyed Ni-Nb and Ni-Ta and Ni-Nb-Ta Powders

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Data

2012-01-01

Autores

Ferraretto, Ana Clara [UNESP]
Trindade Ramos, Erika Coaglia
Ramos, Alfeu Saraiva [UNESP]

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Editor

Trans Tech Publications Ltd

Resumo

This paper reports on the phase transformation during the preparation of Ni-25Nb, Ni-25Ta, Ni-20Nb-5Ta and Ni-15Nb-10Ta (at-%) powders by high-energy ball milling from elemental powders. The milling process was performed in a planetary ball milling using stainless steel balls and vials, rotary speed of 300rpm, and a ball-to-powder of 10:1. To minimize contamination and spontaneous ignition the powders were handled under argon atmosphere in a glove box. The milled powders were characterized by means of X-ray diffraction techniques. Results indicated that the Ni atoms were preferentially dissolved into the Nb (and/or Ta) lattice at the initial milling times, which contributed to change the relative intensity on the diffraction peaks. After the dissolution of Nb (and/or Ta) into the Ni lattice, the Ni peaks were moved to the direction of lower diffraction angles in Ni-25Nb, Ni-25Ta, Ni-20Nb-5Ta, Ni-15Nb-10Ta powders, indicating that the mechanical alloying was achieved.

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Palavras-chave

nickel alloys, mechanical alloying, metastable structures

Como citar

Advanced Powder Technology Viii, Pts 1 and 2. Stafa-zurich: Trans Tech Publications Ltd, v. 727-728, p. 222-226, 2012.