, Volume 44, Issue 8, pp 36–41 | Cite as

Environmental effects on ductile-phase toughening in Nb5Si3-Nb composites

  • Joseph D. Rigney
  • Preet M. Singh
  • John J. Lewandowski
Refractory Metal Research Summary


A variety of materials have been toughened via the addition of a ductile phase. Brittle silicide intermetallics such as Nb5Si3 have been significantly toughened by niobium particles incorporated during in-situ processing techniques. In the work described here, toughness tests conducted on Nb5Si3 were monitored in a scanning electron microscope to view the process of toughening provided by the niobium particles. In particular, the behavior of the ductile phase was monitored and related to the toughness obtained. In an attempt to vary the behavior of the ductile phase, the composite materials were exposed to a variety of gaseous environments and subsequently tested in air. The resulting toughness, resistance-curve behavior, and in-situ results highlight the importance of the behavior of the ductile phase on subsequent properties.


Fracture Toughness Niobium Ductile Phase Unstable Crack Growth Vacuum Heat Treatment 
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Copyright information

© TMS 1992

Authors and Affiliations

  • Joseph D. Rigney
    • 1
  • Preet M. Singh
    • 1
  • John J. Lewandowski
    • 1
  1. 1.Case Western Reserve UniversityUSA

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