|About this Abstract
||1st World Congress on High Entropy Alloys (HEA 2019)
||High Entropy Alloys 2019
||Nanomechanical Behavior of Body-centered Cubic VNbTaMoW Alloy
||Hicham Zaid, Jacob W. Stremfel, Koichi Tanaka, Angel Aleman, Jenn-Ming Yang, Suneel Kodambaka
|On-Site Speaker (Planned)
We report on microstructural and mechanical characterization of a V0.2Nb0.2Mo0.2Ta0.2W0.2 bulk alloy. X-ray diffraction spectra revealed multiple reflections corresponding to a single-phase, body-centered cubic polycrystal with a lattice constant of 0.319 ▒ 0.001 nm. Nanoindentation tests yielded hardness and reduced elastic modulus values of 9 ▒ 1.4 GPa and 207 ▒ 19 GPa, respectively. In situ scanning electron microscopy based uniaxial compression tests conducted at room-temperature on cylindrical pillars of sizes d between 0.3 Ám and 1 Ám revealed that all the pillars undergo plastic deformation. We find that the yield strengths of the pillars increase with decreasing d from 3.3 GPa at d = 1 Ám to 9.0 GPa at d = 0.3 Ám. We attribute the observed behavior to size-dependent variations in displacement burst frequency and slip events. We expect that our results provide new insights into the nanomechanical response of body-centered cubic alloys.