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@ARTICLE{Lau:1008445,
author = {Lau, Alexander and Coenen, Jan Willem and Schwalenberg,
Daniel and Mao, Yiran and Höschen, Till and Riesch, Johann
and Raumann, Leonard and Treitz, Michael and Gietl, Hanns
and Terra, Alexis and Göhts, Beatrix and Linsmeier,
Christian and Theis-Bröhl, Katharina and Gonzalez-Julian,
Jesus},
title = {{B}ulk {T}ungsten {F}iber-{R}einforced {T}ungsten
({W}f/{W}) {C}omposites {U}sing {Y}arn-{B}ased {T}extile
{P}reforms},
journal = {Journal of nuclear engineering},
volume = {4},
number = {2},
issn = {2673-4362},
address = {Basel},
publisher = {MDPI},
reportid = {FZJ-2023-02345},
pages = {375 - 390},
year = {2023},
abstract = {The use of tungsten fiber-reinforced tungsten composites
(Wf/W) has been demonstrated to significantly enhance the
mechanical properties of tungsten (W) by incorporating
W-fibers into the W-matrix. However, prior research has been
restricted by the usage of single fiber-based textile
fabrics, consisting of 150 µm warp and 50 µm weft
filaments, with limited homogeneity, reproducibility, and
mechanical properties in bulk structures due to the rigidity
of the 150 µm W-fibers. To overcome this limitation, two
novel textile preforms were developed utilizing radial
braided W-yarns with 7 core and 16 sleeve filaments (R.B. 16
+ 7), with a diameter of 25 µm each, as the warp material.
In this study, bulk composites of two different fabric types
were produced via a layer-by-layer CVD process, utilizing
single 50 µm filaments (type 1) and R.B. 16 + 7 yarns (type
2) as weft materials. The produced composites were sectioned
into KLST-type specimens based on DIN EN ISO 179-1:2000
using electrical discharge machining (EDM) and subjected to
three-point bending tests. Both composites demonstrated
enhanced mechanical properties with pseudo-ductile behavior
at room temperature and withstood over 10,000 load cycles
between $50–90\%$ of their respective maximum load without
sample fracture in three-point cyclic loading tests.
Furthermore, a novel approach to predict the fatigue
behavior of the material under cyclic loading was developed
based on the high reproducibility of the composites
produced, especially for the composite based on type 1. This
approach provides a new benchmark for upscaling endeavors
and may enable a better prediction of the service life of
the produced components made of Wf/W in the future. In
comparison, the composite based on fabric type 1
demonstrated superior results in manufacturing performance
and mechanical properties. With a high relative average
density $(>97\%),$ a high fiber volume fraction
$(14–17\%),$ and a very homogeneous fiber distribution in
the CVD-W matrix, type 1 shows a promising option to be
further tested in high heat flux tests and to be potentially
used as an alternative to currently used materials for the
most stressed components of nuclear fusion reactors or other
potential application fields such as concentrated solar
power (CSP), aircraft turbines, the steel industry, quantum
computing, or welding tools. Type 2 composites have a higher
layer spacing compared to type 1, resulting in gaps within
the matrix and less homogeneous material properties. While
type 2 composites have demonstrated a notable enhancement
over 150 µm fiber-based composites, they are not viable for
industrial scale-up unlike type 1 composites.},
cin = {IEK-4},
ddc = {620},
cid = {I:(DE-Juel1)IEK-4-20101013},
pnm = {134 - Plasma-Wand-Wechselwirkung (POF4-134)},
pid = {G:(DE-HGF)POF4-134},
typ = {PUB:(DE-HGF)16},
UT = {WOS:001189003700001},
doi = {10.3390/jne4020027},
url = {https://juser.fz-juelich.de/record/1008445},
}