The high strain rate behaviour of two different tungsten-based composites (WBC's) has been investigated using a combination of compression Kolsky bar and high strain rate pressure-shear plate impact experiments. The two materials investigated are a W/(W-Ni-Fe) 'heavy alloy' containing 91 wt.-% W with a W-Ni-Fe matrix/binder phase and a W/Hf composite containing 72 wt.-% W and a Hf matrix/binder phase. For each material, stress strain curves are obtained in compression and shear over the strain rate range of 103/s to 105/s. The flow stresses observed in the W/Hf composite during these dynamic deformations are comparable to those observed in the W/(W-Ni-Fe) material, in spite of the lower tungsten content of the W/Hf composite. Further, the W/Hf composite displays approximately the same degree of strain-rate hardening as the W/(W-Ni-Fe) composite. The observed behaviour of the W/(W-Ni-Fe) composite is compared with the predictions of several phenomenological models for high-rate deformations, including the Johnson-Cook and Zerilli-Armstrong models.
The mechanical properties of tungsten-based composites at very high strain rates
Die mechanischen Eigenschaften von Wolframverbundwerkstoffen bei sehr hohen Umformgeschwindigkeiten
1995
14 Seiten, 17 Bilder, 3 Tabellen, 36 Quellen
Article (Journal)
English
British Library Conference Proceedings | 2006
|