Crespo del Arco, PatriciaHernando Grande, AntonioGarcia Escorial, A.2023-06-202023-06-201994-05-010021-897910.1063/1.358254https://hdl.handle.net/20.500.14352/60120©1994 The American Physical Society. This work has been supported by the Spanish CICYT through projects Mat. 92-0491 and Mat. 92-0405. A.H. is indebted to the BBV Foundation for support. We thank Dr. A. R. Yavari, Dr. A. L. Greer, and Dr. F. Gartner for explaining to us the main features of spinodal decomposition.Experimental results corresponding to the saturation magnetization and coercive field during the decomposition, upon annealing, of bcc and fcc Fe_xCu_(1-x), obtained by mechanical alloying are reported. The overall behavior points out that the decomposition takes place in two steps: (i) at low temperatures a decrease of the saturation magnetic moment as well as an anomalous thermal dependence of coercive field are observed, however, no phase transformation is detected, and (ii) for further annealing temperatures a new phase appears; the magnetization tends to increase and the coercive field abruptly increases. The analysis of the results leads us to conclude that the first step corresponds to a spinodal decomposition. Fluctuations in the local composition give rise to coexistence of adjacent regions with Curie temperature varying continuously in a range of 1000 K across distances of a few nanometers, thus allowing the tailoring of the magnetic nanostructures.engjournal articlehttp://dx.doi.org/10.1063/1.358254http://aip.scitation.orgopen access538.9Fexcu100-X solid-solutionsImmiscible elementsFísica de materialesFísica del estado sólido2211 Física del Estado Sólido