Nano-structured vanadium: processing and mechanical properties under quasi-static and dynamic compression

We have processed fully dense, nano-structured vanadium (V), a bee metal with a moderately high melting temperature (1910 degreesC) by high-energy ball milling followed by two-step consolidation. We have characterized the as-milled powder and the microstructure of the consolidated, fully dense material using X-ray diffraction and transmission electron microscopy. It was found that the grain size of the consolidated V is around 100 nm. Mechanical properties of the nano-structured V were studied under both quasi-static (strain rates in the range of 10(-3)-10(0) s(-1)) and dynamic compression (Kolsky bar, strain rates in the range of similar to10(3) s(-1)). A high-speed camera was used to observe the deformation and failure process of the specimen under dynamic loading. Cracking was observed along the loading axis under quasi-static compression. Under dynamic loading, nano-structured V fails in a very similar manner to nano-structured Fe and metallic glasses, i.e., via shear banding. (C) 2003 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.