A new Cu–2Ag–0.14La alloy is developed to enhance the mechanical property and electrical conductivity with inducement of Ag-rich primary phases and finer nanoscale Ag precipitates. The microstructural evolution and mechanical properties of Cu–2Ag–0.14La and Cu–2Ag alloys obtained by drawing and annealing were then summarized and analyzed. The results indicate that both the yielding and ultimate tensile strengths of annealed Cu–2Ag-0.14La alloy were reinforced after La modification. The average grain sizes of two alloys increase during annealing, but the size ratio (R_{Cu-2Ag-0.14La} / R_Cu-2Ag) dramatically varies with rising the heat temperature, evolving from 70.48% at 400 °C to 43.78% at 650 °C. Meanwhile, it is found that the refined grains sizes in Cu-2Ag-0.14La alloy are closely related to the nano-scale precipitates (~ 450 nm), which hinder the formation of subgrain boundaries at 400 ℃, and impose a stronger pinning effect on boundary migration of recrystallized grains during annealing (≥450 ℃). Consequently, higher hardness and electrical conductivity are contributed by grain refinement and dispersion strengthening of the nanosized phases.

开发了一种新的 Cu-2Ag-0.14La 合金，通过诱导富含 Ag 的初级相和更细的纳米级 Ag 沉淀来提高机械性能和导电性。然后总结和分析了通过拉伸和退火获得的 Cu-2Ag-0.14La 和 Cu-2Ag 合金的显微组织演变和机械性能。结果表明，退火后的 Cu-2Ag-0.14La 合金的屈服强度和极限抗拉强度均在 La 改性后得到增强。两种合金的平均晶粒尺寸在退火过程中增加，但尺寸比（R _{Cu-2Ag-0.14La} / R _Cu-2Ag) 随加热温度的升高而显着变化，从 400 °C 时的 70.48% 演变为 650 °C 时的 43.78%。同时发现Cu-2Ag-0.14La合金中细化的晶粒尺寸与纳米级析出物（~450  nm）密切相关，阻碍了400 ℃下亚晶界的形成，并施加了更强的钉扎效应退火（≥450℃）过程中再结晶晶粒的边界迁移。因此，纳米相的晶粒细化和弥散强化有助于提高硬度和导电性。