| Using a miniature direct impact Hopkinson bar, the high strain rate deformation behaviour of tantalum was determined. The effects of strain rate, grain size, cold working, pre-shocking and alloying (Ta-10W) on the flow stress of tantalum were examined.; A novel method of non-contact heating was developed for the Hopkinson bar specimens. The high strain rate flow stress behaviour was then determined for tantalum and Ta-10W at high temperatures.; True stress-strain curves from these tests were compared to results from the literature and to constitutive equations developed by Qiang. These comparisons support the validity of the test results, but indicate that for tantalum and tantalum alloys, variations in the degree of previous cold working and material purity are extremely important considerations when using miniature specimens. |
