Abstract
The paper reports the effect of addition of small amount of Mg on the mechanical and oxidation properties of Nb–Nb3Si eutectic composites in Nb–Si system under the condition of suction casting. Mg addition increases the volume fraction of primary dendrites of Nb solid solution. This phase contains significant amount of strengthening precipitates. Two different precipitates are identified. The large plate shaped precipitates are that of hcp phase, while fine coherent precipitates have the structure similar to recently identified δ-Nb11Si2 phase. The Mg addition improves both the strength and ductility of the composite at room temperature (∼1.4GPa and ∼5% engineering strain) as well as at 700°C(∼1.2GPa and ∼7% engineering strain). The presence of Mg results in a complex barrier layer which significantly increases the oxidation resistance up to a temperature of at least 1000°C.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.