挤压态Cu-Al_2O_3弥散强化铜合金组织结构与强化机制的定量探讨

Microstructure and Strengthening Mechanism of the Al_2O_3 Dispersion Strengthened Copper Alloy as Hot-extrusion

通过力学性能测试、金相和透射电镜观察等手段研究了热挤压态Cu-0.12 Al2O3弥散强化铜合金的组织与性能．结果表明：挤压态Cu-Al2O3弥散强化铜合金的主要强化机制是细晶强化和弥散强化．细小的Al2O3相钉扎位错，强烈抑制基体的再结晶，造成材料小晶粒、多晶界效应，其平均亚晶粒大小仅为2～4μm，同时对不同强制机制对合金强度的贡献进行了定量计算，计算值与实验值吻合较好．

The structure and property of the Cu-Al2O3 alloy as hot-extrusion was studied by means of mechanical property measurement, OM and TEM observation. The results showed that the strengthening mechanism of the alloy as hot-extrusion was mainly dispersion strengthening and fine-crystal strengthening. The fine Al2O3 could pin up dislocations and effectively restrain matrixes＇ reerystallization, causing fine grain and multigrain boundary. The average size of the subgrains was 2～4 μm. The quantitative research on the strengthening mechanisms of precipitation strengthening was alto discussed.