Abstract
High strength and creep resistance also at high temperature, combined with a high thermal conductivity and high melting point make tungsten (W) an ideal material for highly loaded areas in future fusion reactors. However, as a typical bcc metal tungsten features an intrinsic brittleness up to very high temperature and is prone to operational embrittlement. Tungsten fibre-reinforced tungsten composite (Wf/W) utilizes extrinsic toughening mechanisms similar to ceramic fibre-reinforced ceramics and therefore overcomes the brittleness problem. The properties of the composite are to a large extend determined by the properties of the drawn tungsten wire used as reinforcement fibres. W wire exhibits a superior strength and shows ductile behaviour with exceptional local plasticity. Beside the typical mechanisms observed for ceramic composites the ductile deformation of the fibres is therefore an additional very effective toughening mechanism. Tension tests were used to investigate this phenomenon in more detail. Results show that there is a region of enhanced localized plastic deformation. The specific energy consumption in this region was estimated and used to suggest optimisation options for Wf/W composites.
Highlights
The development of capable materials is essential for sophisticated future energy systems like a fusion reactor
In comparison to the constraint wire in Wf/W the reduction in area is similar to results for moderate testing speeds [15], but larger than for samples tested at very high speeds [7]
Summary and Outlook The large toughness of Wf/W composites is strongly related to the large specific deformation energy and high strength of the tungsten wire used as reinforcing fibre
Summary
The development of capable materials is essential for sophisticated future energy systems like a fusion reactor. Besides the typical mechanisms observed in ceramic composites the ductile deformation of the tungsten wire has been shown as a very effective additional mechanism in as-fabricated Wf/W [15]. In figure 1 typical stress-strain curves of an as-fabricated doped tungsten wire tested at room temperature are shown (similar to the curves shown in [22]).
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: IOP Conf. Series: Materials Science and Engineering
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.
