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arXiv · 0901.1191

Decomposition process in a FeAuPd alloy nanostructured by severe plastic deformation

Xavier Sauvage·Abdelahad Chbihi·Dmitry Gunderov·E. V. Belozerov·A. G. Popov
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Abstract

The decomposition process mechanisms have been investigated in a Fe50Au25Pd25 (at.%) alloy processed by severe plastic deformation. Phases were characterized by X-ray diffraction and microstructures were observed using transmission electron microscopy. In the coarse grain alloy homogenized and aged at $450 ^{circ}\mathrm{C}$, the bcc α-Fe and fcc AuPd phases nucleate in the fcc supersaturated solid solution and grow by a discontinuous precipitation process resulting in a typical lamellar structure. The grain size of the homogenized FeAuPd alloy was reduced in a range of 50 to 100nm by high pressure torsion. Aging at $450 ^{circ}\mathrm{C}$ this nanostructure leads to the decomposition of the solid solution into an equi-axed microstructure. The grain growth is very limited during aging and the grain size remains under 100nm. The combination of two phases with different crystallographic structures (bcc α-Fe and fcc AuPd) and of the nanoscaled grain size gives rise to a significant hardening of the alloy

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Xavier Sauvage, Abdelahad Chbihi, Dmitry Gunderov, E. V. Belozerov, A. G. Popov. 2009-01-09. Decomposition process in a FeAuPd alloy nanostructured by severe plastic deformation. https://doi.org/10.1007/s10853-008-2752-5

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