2020/03/23 by Marcel Glienke, M. Vaidya, Mayur Vaidya +17 · 2 citations
Chemistry · Engineering · Physics and Astronomy · #Advanced Materials Characterization Techniques #Alloy #Analytical Chemistry (journal) #Atmospheric temperature range #Chemistry #Condensed matter physics #Crystallography #FOS: Physical sciences #Grain boundary #Grain boundary diffusion coefficient #High Entropy Alloys Studies #High-Temperature Coating Behaviors #Kinetic energy #Materials Science (cond-mat.mtrl-sci) #Materials science #Metallurgy #Microstructure #Nanotechnology #Physics #Thermodynamics #Transmission electron microscopy #cond-mat.mtrl-sci
paper · pdf · doi:10.48550/arxiv.2003.10157
published in arXiv (Cornell University) (Cornell University) · 17 pages, 11 figures
openalex publication_date 2020/03/23 · arxiv created 2020/04/02 · arxiv updated 2020/04/03 · openalex created_date 2022/07/26 · openalex updated_date 2026/07/28
Grain boundary self-diffusion of 57Co, 51Cr, 59Fe and\n54Mn in a coarse-grained, single-phase fcc CoCrFeMnNi high entropy alloy\nis measured in a wide temperature range of 643 to 1273~K in both C- and B-type\nkinetic regimes after Harrison's classification. The results suggest that the\nproduct of the pertinent segregation factors, s, and the grain boundary\nwidth, \δ, is about 0.5~nm for all elements at temperatures T>800~K.\nWhereas one short-circuit contribution is observed at higher temperatures above\n800~K, the penetration profiles in the C-type kinetic regime (643 -- 703~K)\nreveal two distinct contributions that hint towards a phase decomposition at a\nfraction of high-angle grain boundaries at these temperatures. A correlative\nmicroscopy combining transmission Kikuchi diffraction and atom probe tomography\nmanifests formation of neighbouring Ni-Mn-rich and Cr-rich precipitates at a\nsegment of high angle grain boundaries. Transmission electron microscopy\nrevealed an increased dislocation density in the vicinity of such interfaces\nwhich is suggested to be a reason of the enhanced diffusion rates at low\ntemperatures for such short circuits.\n