Thermally activated deformation mechanisms and solid solution softening in W-Re alloys investigated via high temperature nanoindentation

Thermally activated deformation mechanisms in three different W-Re alloys were investigated by performing high temperature nanoindentation experiments up to 800 °C. With increasing Re content the athermal hardness increases, while the temperature-dependent thermal contribution is strongly decreased....

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Bibliographic Details
Main Authors: Johann Kappacher, Alexander Leitner, Daniel Kiener, Helmut Clemens, Verena Maier-Kiener
Format: Article
Language:English
Published: Elsevier 2020-04-01
Series:Materials & Design
Online Access:http://www.sciencedirect.com/science/article/pii/S0264127520300320
Description
Summary:Thermally activated deformation mechanisms in three different W-Re alloys were investigated by performing high temperature nanoindentation experiments up to 800 °C. With increasing Re content the athermal hardness increases, while the temperature-dependent thermal contribution is strongly decreased. This results in a reduced strain rate sensitivity for W-Re alloys compared to pure W. The origin of this effect is a reduction of the Peierls potential due to Re, manifesting in an increased activation volume at lower temperatures. This gives rise to a solid solution softening effect, while at high-temperature application the mechanical behavior is governed by dislocation-dislocation interaction and solution strengthening. Keywords: Refractory metals, High temperature deformation, Plastic deformation, Strain rate sensitivity
ISSN:0264-1275