Journal Article

FZJ-2019-04809

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Modeling and validation of chemical vapor deposition of tungsten for tungsten fiber reinforced tungsten composites

Raumann, L. (Corresponding author)FZJ* ; Coenen, J. W.FZJ* ; Riesch, J. ; Mao, Y.FZJ* ; Gietl, H. ; Höschen, T. ; Linsmeier, C.FZJ* ; Guillon, O.FZJ*

2020
Elsevier Science84367 Amsterdam [u.a.]

This record in other databases:  

Please use a persistent id in citations: http://hdl.handle.net/2128/23762  doi:10.1016/j.surfcoat.2019.06.065

Abstract: Tungsten is the most promising first wall material for nuclear fusion reactors. One disadvantage, however, is its intrinsic brittleness. Therefore, tungsten fiber reinforced tungsten (Wf/W) is developed for extrinsic toughening. Wf/W can be produced by chemical vapor deposition (CVD), e.g. by reducing WF6 with H2 using heated W-fibers as substrate. However, it still needs to be optimized regarding relative density and fiber volume fraction. The decisive factor is the tungsten deposition rate, which depends on the temperature and the partial pressures. For this dependence, however, there are controversial results in the literature. In this article, a new rate equation is presented, in which different literature equations are partially adapted and combined. It adjusts the WF6 reaction order between one and zero, depending on the temperature and the H2 and WF6 partial pressure. For validation, a simplified experimental setup with a single fiber was designed, which provides very well defined boundary conditions while varying the CVD process parameters heating temperature, pressure, gas flow rate and gas inlet composition. The experimental runs were simulated with COMSOL Multiphysics. The model was successfully validated by measurements of the WF6 consumption rates (< 2 to 100 %), deposited tungsten masses and spatially high-resolved tungsten deposition rates.

---

Contributing Institute(s):

1. Plasmaphysik (IEK-4)

Research Program(s):

1. 113 - Methods and Concepts for Material Development (POF3-113) (POF3-113)
2. EUROfusion - Implementation of activities described in the Roadmap to Fusion during Horizon 2020 through a Joint programme of the members of the EUROfusion consortium (633053) (633053)

Appears in the scientific report 2020

---

Database coverage:
; ; Clarivate Analytics Master Journal List ; Current Contents - Engineering, Computing and Technology ; Ebsco Academic Search ; IF < 5 ; JCR ; Nationallizenz ; SCOPUS ; Science Citation Index ; Science Citation Index Expanded ; Web of Science Core Collection

---