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Creep strength in polycrystalline Ni-based superalloys is influenced by the formation of a rich variety of planar faults forming within the strengthening γ' phase. The lengthening and thickening rate of these faults – and therefore the creep rate – depends on an intriguing combination of dislocation interactions at the γ/γ' interface and diffusional processes of the alloying elements at the core of the fault tip. The effect of alloy composition on this process is not fully understood. In this work we use correlative high resolution transmission electron microscopy and energy-dispersive X-ray spectroscopy to study the deformation faults in two different Ni-based superalloys with carefully designed ratios of disordering-to-ordering-promoting elements (Co-Cr against Nb-Ta-Ti). The results show that the additions of ordering-promoting elements reduce the diffusional processes required for the faults to lengthen and thicken thus reducing the creep rates found for the higher Nb-Ta-Ti alloy. These insights provide a path to follow in the design of improved grades of creep-resistant polycrystalline alloys beyond 700 °C. 

The EIC Comprehensive Chromodynamics Experiment (ECCE) detector has been designed to address the full scope of the proposed Electron Ion Collider (EIC) physics program as presented by the National Academy of Science and provide a deeper understanding of the quark–gluon structure of matter. To accomplish this, the ECCE detector offers nearly acceptance and energy coverage along with excellent tracking and particle identification. The ECCE detector was designed to be built within the budget envelope set out by the EIC project while simultaneously managing cost and schedule risks. This detector concept has been selected to be the basis for the EIC project detector. 

A<sc>bstract</sc> We report multi-differential measurements of strange hadron production ranging from mid- to target-rapidity in Au+Au collisions at a center-of-momentum energy per nucleon pair of$$ \sqrt{s_{\textrm{NN}}} $$ $\sqrt{s_{\mathrm{NN}}}$= 3 GeV with the STAR experiment at RHIC.$$ {K}_S^0 $$ $K_S^0$meson and Λ hyperon yields are measured via their weak decay channels. Collision centrality and rapidity dependences of the transverse momentum spectra and particle ratios are presented. Particle mass and centrality dependence of the average transverse momenta of Λ and$$ {K}_S^0 $$ $K_S^0$are compared with other strange particles, providing evidence of the development of hadronic rescattering in such collisions. The 4πyields of each of these strange hadrons show a consistent centrality dependence. Discussions on radial flow, the strange hadron production mechanism, and properties of the medium created in such collisions are presented together with results from hadronic transport and thermal model calculations.