Abstract
Dense W and W–Zr composites reinforced with Sc2O3 particles were produced through powder metallurgy and subsequent spark plasma sintering (SPS) at 1700 °C and 58 MPa. Results showed that the W–1vol.%Zr/2vol.%Sc2O3 composites exhibited optimal performance with the best relative density of up to 98.93% and high Vickers microhardness of approximately 583 Hv. The thermal conductivity of W–Zr/Sc2O3 composites decreased initially and then increased as the Zr content increased. The moderate Zr alloying element could combine well with Sc2O3 particles and W grains and form a solid solution. However, excess Zr element leads to agglomeration in the grain boundaries. W–1vol.%Zr/2vol.%Sc2O3 composite had a good deuterium irradiation resistance very closing to pure tungsten compared with the other Zr element contents of composites. Under 500 K, D2 retention and release of them were similar to those of commercial tungsten, even lower between 400 K to 450 K. Pre-irradiation with 5 keV-He+ ions to a fluence of 1 × 1021 He+/m2 resulted in an increase in deuterium retention (deuterium was implanted after He+ irradiation), thereby shifting the desorption peak to a high temperature from 550 K to 650 K for the W–1vol.%Zr/2vol.%Sc2O3 composite.
Highlights
Dense W and W–Zr composites reinforced with Sc2O3 particles were produced through powder metallurgy and subsequent spark plasma sintering (SPS) at 1700 °C and 58 MPa
W, Sc2O3, ZrH2, and the as–prepared powders were observed through Field emission scanning electron microscope (FE–SEM) equipped with energy dispersive X-ray spectroscopy (EDS)
After the ball milling for 40 h in a vacuum condition, the average particle size of the mixed powder decreased obviously comparing with the medium particle diameter
Summary
VW, VZr, and VSc2O3 are the volume fractions of W, Zr, and Sc2O3, respectively, whereas CPW, CPZr, and CPSc2O3 are the specific heat values of W, Zr, and Sc2O3, respectively. The W–Zr/Sc2O3 composites were mechanically polished until the surface was mirror-like. W–1vol.%Zr/2vol.%Sc2O3 composites were exposed to He+ ions with a fluence of 1 × 1021 He+/m2 and subsequent D2 ions with a fluence of 1 × 1020 D2+/m2. After these ion implantations, TDS measurements were performed from room temperature (RT) to 900 K via infrared irradiation with a heating rate of 1 K/s to investigate the D retention behavior. Transmission electron microscopy (TEM; JEM–2100F, Japan) was performed to observe the microstructure of the SPS-sintered W–5vol.%Zr/2vol.%Sc2O3 composite prepared with ion-thinning technology because of its highest second phase content which was easier to observe. The grain sizes were measured from the SEM images of the fractured surface morphology of the SPS-sintered samples
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 call
