Berlin 2015 – wissenschaftliches Programm
MM 28.29: Poster
Dienstag, 17. März 2015, 18:30–20:30, Poster E
Hot Isostatic Pressed Tungsten Fiber-Reinforced Tungsten — •Bruno Jasper1, Jan W. Coenen1, Johann Riesch2, Till Höschen2, and Christian Linsmeier1 — 1Forschungszentrum Juelich GmbH, IEK4 - Plasmaphysik, 52425 Jülich, Germany — 2Max-Planck-Institut für Plasmaphysik, 85748 Garching, Germany
Tungsten fiber-reinforced tungsten (Wf/W) is a composite material that addresses the brittleness of tungsten (W) at low temperatures and after operational embrittlement, through extrinsic toughening by introducing crack energy dissipation mechanisms. Existing Wf/W samples produced via chemical vapor infiltration indeed showed higher toughness in mechanical tests than pure W. In this contribution Wf/W material specimens produced via powder metallurgical (PM) methods, e.g. hot isostatic pressing (HIP), are shown. A variety of measurements, e.g. 3-point bending and push-out tests, are presented to verify the operation of the expected toughening mechanisms. Therefore the focus of the investigations lies on the interface deboning behavior. In particular, the stability and integrity of the interface is investigated, since high temperatures (up to 1900 ∘C) and pressures (200 MPa) are present during the composite preparation. First HIP single-fiber samples indicate a compact matrix with densities of 99+ % of the theoretical density of W and showed signs of recrystallization and grain growth. SEM analysis demonstrates an intact interface with indentations of powder particles at the interface-matrix boundary. Push-out test results indicate that the structure of the interface may be damaged by HIPing since push-out of matrix elements is observed.