中文摘要：

利用透射电子显微镜和光学显微镜研究了窀温下1～8道次等通道角挤压（ECAP）3工艺对TiAl3-P／Al复合材料组织的影响。结果表明，在ECAP挤压初期Al基体中的位错密度很高，在2道次后急剧降低；组织中位错墙比例在开始也呈现升高的趋势，随着应变量的增加，逐渐向小角度晶界转变；小角度晶界的出现比位错墙晚，晶内小角度晶界的比例变化趋势也是一个先增加后降低的过程，最终转变为大角晶界。ECAP过程中，TiAl3颗粒对Al基体组织变化的作用不明显。ECAP变形有效破碎了较大尺寸的TiAl3颗粒并改善了TiAl3颗粒在Al基体中分布的均匀度。板条状TiAl3在ECAP变形中不仅发生了脆性断裂，还发生了孪生变形，与基体金属的变形相互协调，使少量大尺寸TiAl3颗粒保留下来。

英文摘要：

The microstructures of TiAl3-P/Al composites processed by equal channel angular extrusion （ECAP） at room temperature, to an equivalent strain up to 8, were studied by transmission electron microscopy （TEM） and optical microscopy （OM）. The results show that the density of dislocations in Al matrix increases after one ECAP pass, but then decreases dramatically after two passes. With increasing strain, dislocation walls transform firstly into low angular grain boundaries, but then into high angular grain boundaries. In the process of ECAP TiAl3 particles have no obvious effects on the evolution of microstructures of AI matrix. ECAP deformation breaks the larger TiAl3 particles effectively. With increasing ECAP pass, TiAl3 particles distribute more homogeneously in Al alloy matrix. Twinning deformation is found in lath-shaped TiAl3 after 8 ECAP passes except brittle fracture, which is consistent with the deformation of the matrix metal, and it keeps a few of larger TiAl3 particles without totally broken.