采用等通道转角挤压(ECAP)技术改良了传统挤压模具分流孔;通过螺旋槽焊合模腔,挤出了壁厚2 mm的管材。研究了镁合金的组织变化及材料的性能。结果表明:挤压态合金组织均匀,晶粒细小(平均晶粒尺寸约为12.5μm)。等通道转角挤压的细化晶粒过程、动态再结晶以及退火再结晶使合金具有良好的组织结构和力学性能。挤压态试样断口呈现为脆性解理断裂方式,退火态试样断口则表现为脆性和韧性混合断裂机制。 Equal channel corner extrusion (ECAP) technique was used to improve the traditional extrusion die orifice; the 2 mm thick pipe was extruded through the cavity by spiral groove. The microstructure and properties of magnesium alloy were studied. The results show that the as-extruded alloy has uniform microstructure and fine grains (the average grain size is about 12.5μm). The process of grain refinement, such as dynamic recrystallization and annealing recrystallization, make the alloy have good structure and mechanical properties. Extruded specimens show a brittle cleavage fracture mode, and annealed fracture specimens show brittle and ductile mixed fracture mechanism.