研究了Cu⁃2．7％Al2 O3弥散强化铜（ ADSC）合金的微观组织和力学性能。研究表明，纳米级的Al2 O3弥散分布在铜基体中，多数为近球形，在晶界处有部分粗大的Al2 O3粒子存在。 Al2 O3粒子与位错的交互作用以及霍尔⁃佩奇机制的贡献占其室温屈服强度的90％，高温下合金的强度主要与Al2 O3粒子对位错的强烈钉扎以及对晶界和亚晶界滑动的阻碍作用有关。该合金的室温抗拉强度超过了560 MPa，700℃下的强度几乎与纯铜在室温下的强度相当。不同温度下的拉伸断口分析表明，弥散强化铜（ ADSC）合金的塑性随温度升高逐渐降低。该合金的可加工性能优良，旋锻加工后，垂直于加工方向的晶粒进一步细化，平行于加工方向的纤维组织进一步拉长，横向和纵向硬度值均在160±5 Hv范围内。%The microstructure and mechanical properties of Cu⁃2. 7%Al2 O3 dispersion strengthened copper ( ADSC ) alloy were investigated. The results indicated that nano⁃Al2 O3 particles, most of which are nearly spherical, dispersively distributed in the matrix copper, with some coarse ones distributed at the grain boundaries. The strength contributed by the interaction of dislocations with Al2O3 particles and Hall⁃Petch mechanism accounted for 90% of the yield strength of the alloy at room temperature. The high⁃temperature strength of the alloy was attributed to the strong pinning effect of the alumina particles on dislocations and the impediment to the sliding of grain and sub⁃grain boundaries. The tensile strength of the alloy was over 560 MPa at room temperature, and the strength was almost equivalent to that of pure copper at 700 ℃. Analysis of tensile fracture at different temperatures indicated that the plasticity of ADSC alloy decreased with the increasing of testing temperature. The ADSC alloy obtained excellent workability. After rotary swaging operation, the grains perpendicular to the machining direction were further refined, while the fibrous tissue parallel to the machining direction was further elongated, resulting in the horizontal and vertical hardness values within 160±5 Hv.
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