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In this study, the effect of accelerated Fe-rich precipitation caused by Ag addition on the refinement of solidified microstructure and the improvement of electrical, mechanical, and magnetic properties of Cu–10Fe alloys was systematically investigated. Firstly, the quadruple refinement of Cu grains, micron-sized primary Fe-rich spheres and dendrites, and nano-sized Fe-rich precipitates in as-cast Cu–10Fe alloys was induced by the accelerated Fe-rich precipitation. Secondly, the saturation magnetization of as-cast Cu–10Fe alloys was improved, which is mainly dominated by the accelerated precipitation of micron-sized Fe-rich spheres and dendrites, rather than that of nano-sized Fe-rich precipitates. Moreover, the yield strength of cold-rolled Cu–10Fe alloys was increased, which can be attributed to the accelerated precipitation of nano-sized Fe-rich phases and their pinning effect on dislocation movement during cold-rolling. In the end, the synergistic enhancement of strength, ductility, and electrical conductivity of aged Cu–10Fe alloys was obtained by Ag addition, which guides the preparation of high-performance Cu–Fe alloys. [ABSTRACT FROM AUTHOR]

Processing of immiscible alloys with a homogeneous distribution of fine minor segregated phases is a great challenge. Al-10 wt.%Bi immiscible alloys were solidified under the homogeneous and gradient high magnetic fields (HHMF and GHMF). X-ray computed tomography technique was applied to study the spatial features of the minor Bi-rich particles (MBPs). The results show that the MBPs displayed as centripetal and centrifugal distributions along the radial directions of the ingots solidified under the GHMF. The segregation of the minor Bi-rich droplets (MBDs) was dominated by both radial Marangoni migration and the vertical Stokes sedimentation under the HHMF. In the case of the GHMF, both the radial Marangoni migration and vertical Stokes sedimentation of the MBDs can be effectively stopped by the gradient forces. This work provides a novel path to design the novel alloys with homogeneous microstructures by utilizing the magneto-Archimedes levitation. [Display omitted] [ABSTRACT FROM AUTHOR]

• The excellent mechanical properties produced by refined grains can be inherited. • Strengthening mechanism of the as-cast and aged samples is changed. • Dislocation and precipitation strengthening play a dominate role in aged samples. In this investigation, a novel heredity phenomenon was reported that the mechanical properties of thermo-mechanically processed Cu-15Ni-8Sn alloys were improved by refining the as-cast structure. This underlying mechanism of hereditary strengthening was carefully analyzed, which is mainly contributed to the additional dislocation proliferation induced by structure refinement and accelerated precipitation effect on strengthening phases. The strengthening mode changed from grain refinement strengthening in as-cast state to dislocation strengthening and precipitation strengthening for aged alloys. [ABSTRACT FROM AUTHOR]

The effects of Zr addition on the solidification structure and mechanical properties of a Cu-10 wt%Fe alloy were investigated. Grain refinement results from the in-situ synthesis of the ZrFe 2 nucleation substrate during solidification. The enhanced mechanical properties can be attributed to the additional precipitation of Cu 4 Zr and ZrFe 2 during ageing. [ABSTRACT FROM AUTHOR]

The mechanical and electrical properties of continuously cast Cu-0.4 wt%Te alloy produced by continuous extrusion forming at 800 °C were investigated. It was found that this thermomechanical processing was an effective way to induce the formation of refined recrystallized grain and promote dynamic precipitation of Te atom, thereby simultaneously improving the strength, ductility and electrical conductivity of Cu-0.4 wt%Te alloy. • Ultrafine grained Cu-0.4Te alloy obtained by continuous extrusion forming at 800 °C (termed as HCEF process). • Refined recrystallized grain with high coordinated deformation ability significantly increase the strength-ductility. • Dynamic precipitation during HCEF process was accelerated due to the high activation energy at elevated temperature. • Improved precipitation of Te atom in Cu matric induced the increase in electrical conductivity of Cu-0.4Te alloy. [ABSTRACT FROM AUTHOR]