Abstract
Reactions during compaction of Mo/Mo silicide wires with and without Nb interlayers were qualitatively assessed in this work. It appeared that hot pressing at 1800 °C/60 minutes/30 MPa in vacuum had not been sufficient to compact the Mo/Mo silicide wires in the absence of any additional interfacial layer. However, the development of silicide layers proceeded and the redistribution of elements towards equilibrium took place.
Hot pressing of Mo/Mo silicide + Nb wires yielded compact composites with little pores and cracks. Interfacial reactions resulted in the decomposition of MoSi₂ followed by forming of Nb₅Si₃ silicide.
Best results were achieved with 3 μm thick Nb foils, yielding compact interfaces with limited development of new phases. Low amount of Nb resulted in only partial decomposition of MoSi₂ to Mo₅Si₃ followed by forming of thin (Nb, Mo)₅Si₃ ternary silicide.

Key words
Mo silicides, Nb silicides, composite materials, Si infiltration, hot pressing

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