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arXiv · 2010.11798

On the Brittle-to-Ductile Transition of the As-cast TiVNbTa Refractory High-entropy Alloy

Robert James Scales·David Edward John Armstrong·Angus J Wilkinson·Bo-Shiuan Li
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Abstract

The fracture properties of as-cast TiVNbTa, a refractory high-entropy alloy (RHEA), were investigated using four-point bending tests from -139C to 20C under a strain-rate of 10-3 s-1. From those tests and fractography, the conditional fracture toughness values and the brittle-to-ductile transition temperature were obtained. The brittle-to-ductile transition temperature was between -47C to -27C, which gives an estimated activation energy value of 0.52+-0.09 eV for the alloy. This study provides a preliminary understanding of the nature of dislocation motion in a relatively ductile RHEA.

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Robert James Scales, David Edward John Armstrong, Angus J Wilkinson, Bo-Shiuan Li. 2020-10-22. On the Brittle-to-Ductile Transition of the As-cast TiVNbTa Refractory High-entropy Alloy. https://doi.org/10.1016/j.mtla.2020.100940

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