Evolution of the Structure and Magnetic Properties of Composite Powder Co-Cu during Mechanical Alloying
R. S. ISKHAKOV1, L. A. KUZOVNIKOVA2, S. V. KOMOGORTSEV1, E. A. DENISOVA1, V. K. MALTSEV1 and G. N. BONDARENKO3
1Kirensky Institute of Physics, Siberian Branch of the Russian Academy of Sciences,
Akademgorodok, Krasnoyarsk 660036 (Russia) Г…-mail: rauf@iph.krasn.ru
2Irkutsk State Transport University, Krasnoyarsk Branch,
Ul. L. Ketskhoveli 89, Krasnoyarsk 660028 (Russia)
3Institute of Chemistry and Chemical Technology, Siberian Branch
of the Russian Academy of Sciences, Ul. K. Marksa 42, Krasnoyarsk 660049 (Russia)
Pages: 209-216
Abstract
Comparative investigation of the process of mechanochemical preparation of supersaturated solid solutions is carried out with the composite powders (Co-P)100-x/Cux, which are fine particles with the nucleus composed of amorphous Co88P12 alloy or crystal alloy Co95P5 coated with a copper layer, and a mixture of Co-P and Cu powders. The changes in structural and phase state of the powders during mechanical alloying are investigated by means of electron microscopy, X-ray diffraction, magnetic measurements and NMR spectroscopy. It is shown that mechanical alloying (MA) of the powder of composite particles with amorphous nuclei proceeds much more rapidly than with a similar powder with crystalline nuclei or mechanical mixtures of Co and Cu powders. It is established that MA in Co-P/Cu system with the mass concentration of copper 20 % (a thin Cu coating) passes through amorphization stage. In the case of composite powders (Co88P12)50/Cu50 (with an increased thickness of Cu coating) crystallization of the Co-P nucleus is observed at the start of MA process, then the formation of equimolar supersaturated solid solution occurs.
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