Mechanical Alloying of Zr-Nb5%at. Powders: Microstructural Evolution and Hydrogenation Properties


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Zircaloy is commonly applied as structural element in nuclear reactors owing to the gamma radiation transparency of Zr. One of the research interests in Zr-Nb alloys is related to its behavior in H2O-rich environments due to hydrogen embrittlement. In the present work the microstructural evolution (crystallite size and microhardness), crystallography and hydrogenation behavior (after milling) due to mechanical alloying (MA) are studied for the Zr-Nb5%at and pure Zr. The MA study of Zr and the Zr-Nb system showed that frequency of rotation in a planetary mill and alloy composition play a major role on the evolution of crystallite size and microhardness. Nb addition was found to induce a partial allotropic transformation of the Zr structure (α→ω) during MA. Indeed, for milling experiments with significant Fe contamination the formation of an fcc phase was observed. Further, MA for extended times (over 5 hours) was found to reduce the hydrogen absorption capacity of Zr and the Zr-Nb system studied.



Edited by:

Dílson S. dos Santos




S.A. Loureiro et al., "Mechanical Alloying of Zr-Nb5%at. Powders: Microstructural Evolution and Hydrogenation Properties", Materials Science Forum, Vol. 570, pp. 59-64, 2008

Online since:

February 2008




[1] P. Villars: Pearson's Handbook, Desk Edition: Crystallographic Data for Intermetallic Phases (American Society for Metals, Metals Park, OH, USA, 2001).

[2] Y. Zhao, J. Zhang, C. Pantea, et al.: Physical Review B Vol. 71 (2005), p.1098.

[3] J. Zhang, Y. Zhao, C. Pantea, et al.: Journal of Physics and Chemistry of Solids Vol. 66 (2005), p.1213.

[4] P.P. Chattopadhyay, I. Manna, S. Talapatra, et al.: Materials Chemistry and Physics Vol. 68 (2001), p.85.

[5] I. Manna, P.P. Chattopadhyay, F. Banhart, H.J. Fecht: Applied Physics Letters Vol. 81 (2002), p.4136.

[6] P. Karen, P.M. Woodward: Journal of Solid State Chemistry Vol. 141 (1998), p.78.

[7] G.B. Schaffer, P.G. McCormick: Metallurgical Transactions A Vol. 23A (1992), p.1285.

[8] S.A. Loureiro, A.Z. Salustiano, D.S. dos Santos, L.M. Tavares: Journal of Physics and Chemistry of Solids, submitted.

[9] F. Delogu, M. Monagheddu, G. Mulas, L. Schiffini, G. Cocco: J. Non-Cryst. Solids Vol. 232- 234 (1998), p.383.


[10] C.C. Koch: Nanostructured Materials Vol. 9 (1997), p.13.