Composition evolution of gamma prime nanoparticles in the Ti-doped CoFeCrNi high entropy alloy

L12-strengthened high-entropy alloys for advanced structural applications

“…Moreover, Han et al successfully studied the compositional evolution of the metastable L1 2 -nanoparticles in (CoFeCrNi)Ti 0.2 HEA as a function of aging time at 800°C. 58 It was found that Co atom rapidly reaches a stable concentration in the early stage of the precipitation, whereas Fe and Cr atoms are incorporated into the L1 2 nanoparticles during the coarsening process. The APT results were well supported by the firstprinciples calculations from a perspective of electronic state.…”

Exceptional nanostructure stability and its origins in the CoCrNi-based precipitation-strengthened medium-entropy alloy

“…Precipitation-hardened high-entropy alloys (HEAs) and medium-entropy alloys (MEAs) containing coherent nanoprecipitates have gained increasingly research interests due to their superior combination of strength and ductility [1][2][3][4][5][6][7][8]. Their outstanding mechanical performances at ambient temperature could be attributed to a joint effect of precipitation hardening from the nanoparticles and high work-hardening capability of the matrix [5,8].…”

“…All of these are of utmost importance for the optimized compositional design and also performance enhancement. However, although there have been some experimental studies regarding the partitioning and site preference of different solute elements in the complex HEA and MEA systems [4,8], rather limited literature is available on the temporal information of the microstructure stability and precipitation kinetics. More recently, Zhao et al reported that the coarsening rate of γ nanoparticles in the (NiCoCrFe) 94 Al 4 Ti 2 (at.…”

Elemental Phase Partitioning in the γ-γ″ Ni2CoFeCrNb0.15 High Entropy Alloy

“…Although the energy dispersive X-ray spectroscopy (EDS) equipped on scan electron microscope (SEM) or on transmission electron microscope (TEM) has been widely used to determine the material composition, it is difficult to distinguish the composition of the nanoparticles from that of the surrounding matrix. Atom probe tomography (APT), the only technique which can generate the three-dimensional (3D) atom maps of materials in the real space with nearly atomic-scale resolution, has been proved to be a powerful method of characterizing the composition of different kinds of nanoparticles [ 15 , 18 , 21 , 22 ]. Recently, we have successfully clarified the partitioning of the alloying elements into the γ′ nanoparticles in the NiFeCoCrTi 0.2 HEA by APT [ 22 ].…”