Texture development in Cu-Ag-Fe triphase immiscible nanocomposites with superior thermal stability

Nanocrystalline metals attract intensive interests due to their high strength, excellent wear resistance and superior radiation. However, grain coarsening at elevated temperatures can lead to significant property degradation, impairing their potentials for high temperature applications. Here, we report a unique interplay of immiscible Cu, Ag, Fe grains in stabilizing the grain structure and tailoring the texture development. The Cu ₅₀Ag ₅₀ alloy experiences drastic grain coarsening after annealing at 600 °C and 700 °C. In contrast, the Cu-Ag-Fe nanocomposites exhibit much smaller grain size upon annealing. Interestingly, while the Cu ₅₀Ag ₅₀ alloy displays random nanocrystal orientation, highly textured Cu-Ag-Fe nanocomposites form. Furthermore, the composition of Fe plays a dominant role in changing the texture of nanocomposites from (111) Ag (Cu) and (110) Fe in Cu ₄₅Ag ₄₅Fe ₁₀, to prominent (110) Ag (Cu) and (100) Fe in Cu ₃₃Ag ₃₃Fe ₃₄. The fundamental mechanisms behind the texture formation and evolution are discussed. This study provides a fresh perspective to the design of stable nanocomposites with tunable texture.