Fig. 1. Microhardness and electrical conductivity of specimens treated with different conditions.

Fig. 2. Experimental device and the cross-sectional microstructure of Cu-Cr-Zr alloy under different conditions. (a) Schematic illustration of the CEF and aging process; (b) as-cast; (c) continuously extruded; (d) aged.

Fig. 3. Misorientation distributions of grain/subgrain boundaries in the Cu-Cr-Zr alloy under different conditions. (a) As-cast; (b) continuously extruded; (c) aged for 3 h.

Fig. 4. The GOS maps of the extruded and aged specimens. (a) Extruded; (b) the microstructure with the GOS value between 0°-1° in the extruded specimen; (c) aged; (d) the microstructure with the GOS value between 0°-1° in the aged specimen.

Fig. 5. Tensile strength of the specimens treated with different conditions.

Fig. 6. Friction behavior of all processed specimens: (a) friction coefficient curves; (b) average friction coefficient; (c) weight loss; (d) wear rate.

Fig. 7. Wear resistance of all processed specimens: (a) 3D profilometric images of wear tracks; (b) wear track profiles; (c) width and depth of wear track.

Fig. 8. SEM images of worn surfaces of the specimens with and without modification: (a-c) as-cast; (d-f) extruded; (g-i) aged.

Fig. 9. Bright- and dark-field TEM images of the specimens processed by the CEF and subsequent aging: (a, b) extruded specimen; (c, d) Aged specimen. The insets are the corresponding selected area electron diffraction (SAED) patterns.

Fig. 10. A high-resolution TEM image of the Cr precipitate in the aged specimen: (a) Cr precipitate in the matrix and the inset shows the FFT image along a [111] zone axis of Cr; (b) EDS of the area in (a).

Fig. 11. Strengthening mechanism of Cu-Cr-Zr alloy. (a) Schematic illustration of the architected structure by the CEF and subsequent aging treatment; (b) quantification of strengthening contributions.

Fig. 12. SEM images of subsurface morphologies of all processed specimens: (a) as-cast specimen; (b) extruded specimen; (c) aged specimen; (d) the thicknesses of the mechanical mixing layer and plastically deformed layer.

Fig. 13. Subsurface microhardness measured by nanoindentation: (a) SEM image of the subsurface of as-cast specimen; (b) as-cast specimen; (c) extruded specimen; (d) aged specimen.

Fig. 14. Intrinsic material parameters of all processed specimens measured by nanoindentation: (a) load-displacement curves; (b) required load for achieving an indentation depth of 1000 nm; (c) microhardness and reduced elastic modulus; (d) H/Er and H3/Er2.