Component-dependent lattice distortions and atomic scale insights in multi-component Au-Cu-Ni-Pd-Pt based alloys  

作　　者：Sophie Drescher Alexei Kuzmin Edmund Welter Jens Freudenberger Alevtina Smekhova 

机构地区：[1]Leibniz Institute for Solid State and Materials Research,D-01069 Dresden,Germany [2]TU Bergakademie Freiberg,Institute of Materials Science,D-09599 Freiberg,Germany [3]Institute of Solid State Physics,University of Latvia,LV-1063 Riga,Latvia [4]Deutsches Elektronen-Synchrotron(DESY),A Research Centre of the Helmholtz Association,D-22607 Hamburg,Germany [5]Helmholtz-Zentrum Berlin für Materialien und Energie(HZB),D-12489 Berlin,Germany

出　　处：《Nano Research》2025年第2期418-431,共14页纳米研究(英文版)

摘　　要：In our study,the composition-dependent effects of atomic displacementsin Au-Cu-Ni-Pd-Pt basedalloys,comprising elements with large differences in atomic radii,are investigated at the atomic scale.Two alloys-the equimolar AuCuNiPdPt and AuCuNiPd-have been characterized using multi-edge extended X-ray absorption fine structure(EXAFS)spectroscopy in conjunction with reverse Monte Carlo(RMC)simulations at room temperature.The statistically-averaged component-dependent pair distribution functions(PDFs),which represent the distribution of atoms around the assumed regular face-centered cubic(fcc)lattice positions,reveal a shift of their peaks to shorter distances and a pronounced asymmetry in atomic distribution only for atoms with small radi(Cu/Ni).The analysis demonstrates that small atoms(Cu/Ni)are significantly more displaced from the expected lattice positions as compared to large atoms(Au/Pt).Furthermore,there are indications of preferential next-neighbour bonding that changes depending on the alloy composition.The most pronounced changes in the PDFs were found solely for Pd.With this study,we provide a basis for a deeper understanding of the composition-dependent atomic arrangement in chemically complex solid solutions.

关 键 词：high-entropy alloys short-range order solid solution strengthening extended X-ray absorption fine structure(EXAFS)spectroscopy reverse Monte Carlo 

分 类 号：TG132[一般工业技术—材料科学与工程]