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Nanocrystalline and nanolaminated materials show enhanced radiation tolerance compared with their coarse-grained counterparts, since grain boundaries and layer interfaces act as effective defect sinks. Although the effects of layer interface and layer thickness on radiation tolerance of crystalline nanolaminates have been systematically studied, radiation response of crystalline/amorphous nanolaminates is rarely investigated. In this study, we show that irradiation can lead to formation of nanocrystals and nanotwins in amorphous CuNb layers in Cu/amorphous-CuNb nanolaminates. Substantial element segregation is observed in amorphous CuNb layers after irradiation. In Cu layers, both stationary and migrating grain boundaries effectively interact with defects. Furthermore, there is a clear size effect on irradiation-induced crystallization and grain coarsening. In situ studies also show that crystalline/amorphous interfaces can effectively absorb defects without drastic microstructural change, and defect absorption by grain boundary and crystalline/amorphous interface is compared and discussed. Our results show that tailoring layer thickness can enhance radiation tolerance of crystalline/amorphous nanolaminates and can provide insights for constructing crystalline/amorphous nanolaminates under radiation environment. 

Self-assembled vertically aligned metal–oxide (Ni–CeO 2 ) nanocomposite thin films with novel multifunctionalities have been successfully deposited by a one-step growth method. The novel nanocomposite structures presents high-density Ni-nanopillars vertically aligned in a CeO 2 matrix. Strong and anisotropic magnetic properties have been demonstrated, with a saturation magnetization ( M s ) of ∼175 emu cm −3 and ∼135 emu cm −3 for out-of-plane and in-plane directions, respectively. Such unique vertically aligned ferromagnetic Ni nanopillars in the CeO 2 matrix have been successfully incorporated in high temperature superconductor YBa 2 Cu 3 O 7 (YBCO) coated conductors as effective magnetic flux pinning centers. The highly anisotropic nanostructures with high density vertical interfaces between the Ni nanopillars and CeO 2 matrix also promote the mixed electrical and ionic conductivities out-of-plane and thus demonstrate great potential as nanocomposite anode materials for solid oxide fuel cells and other potential applications requiring anisotropic ionic transport properties. 

Solid solutions of Mg 2 Si and Mg 2 Sn are promising thermoelectric materials owing to their high thermoelectric figures-of-merit and non-toxicity, but they may undergo phase separation under thermal cycling due to the presence of miscibility gaps, implying that the thermoelectric properties could be significantly degraded during thermoelectric device operation. Herein, this study investigates the strain-induced suppression of the miscibility gap in solid solutions of Mg 2 Si and Mg 2 Sn. Separately prepared Mg 2 Si and Mg 2 Sn powders were made into (Mg 2 Si) 0.7 (Mg 2 Sn) 0.3 mixtures using a high energy ball-milling method followed by spark plasma sintering. Afterwards, the phase evolution of the mixtures, depending on thermal annealing and mixing conditions, was studied experimentally and theoretically. Transmission electron microscopy and X-ray diffraction results show that, despite the presence of a miscibility gap in the pseudo-binary phase diagram, the initial mixture of Mg 2 Si and Mg 2 Sn evolved towards a solid solution state after annealing for 3 hours at 720 °C. Thermodynamic analysis as well as phase-field microstructure simulations show that the strain energy due to the coherent spinodal effect suppresses the chemical spinodal entirely and prevents phase separation. This strategy to suppress the miscibility gap induced by lattice strain through non-equilibrium processing can benefit the thermoelectric figure-of-merit by maximizing phonon alloy scattering. Furthermore, stable solid solutions by engineering phase diagrams have the potential to facilitate the reliable long term operation of thermoelectric generators under continuous thermal loads.