ISSN:
1573-4889
Keywords:
Fe-Ni-S system
;
Cu-Ni-S system
;
displacement reaction
;
diffusion path
;
ternary diffusion
;
multiphase diffusion
Source:
Springer Online Journal Archives 1860-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Abstract Solid-state displacement reactions of the type A+BS→B+AS have been studied in the systems Fe-Ni-S and Cu-Ni-S. In diffusion couples, mainly of the type Fe/Ni3S2 and Cu/Ni3S2, the layer sequence, morphology, and growth rate of the reaction products have been investigated. The layer sequence of the reaction products in the couples appears to be just the reverse of that found previously in displacement reactions in some couples of oxide systems like Ni/Cu2O and Co/Cu2O. We find the sequence A/B/AS/BS, whereas in the oxide systems the sequence A/AO/B/BO has been found. This means that the metal atoms exchange and sulfide ions practically stand still in the first case, whereas in the oxide system the transport of oxygen is essential. For a correct interpretation of the results it was necessary to determine the isothermal cross-section through the Fe-Ni-S system at 460 and 500°C. At 500°C the iron stabilized high-temperature modification β-Ni3S2 was found.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00656902
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