Nickel and cobalt silicides

Hence, none of the two above-mentioned criteria can be used as a reliable basis for predicting the sequence of occurrence of chemical compound layers in multiphase binary systems. The experimental data on the formation of nickel and cobalt silicides provides additional evidence for the validity of this conclusion. 

If formed through reactions between elementary substances, close values are obtained for NiAl3 (3.6 %), TaAl3 (4.9 %), TiAl3 (4.2 %) and ZrAl3 (4.8 %). The relative volume decrease is much greater for NiAl (12.7%) and NiBi (17.6%). For nickel and cobalt silicides, its value exceeds 20 %. 

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