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采用ECAP方法对TWIP钢（30Mn-3Si-3Al）试样进行一道次等径角挤压（ECAP）变形，对比研究原始态、一道次挤压态、ECAP1P+850℃×1h/A.C和ECAP1P+1000℃×1h/A.C处理后的微观结构和力学性能。试验结果表明：在变形过程中，由于形变孪晶的相互变形阻力和位错在形变孪晶界的大量塞积，使得TWIP钢表现出很高的加工硬化率。ECAP1P+1000℃×1h空冷处理，在强度不变的情况下塑性较初始态有一定提高。同时，晶粒的长大增加了位错沿孪晶界方向的剪切通道长度，增强了位错储存能力，从而表现出更高的塑性和加工硬化能力。ECAP1P+850℃×1h空冷处理，由于晶粒尺寸较小，增加了阻碍位错运动的有效界面，从而提高了加工硬化能力。

After adopting the deformation of a TWIP steel sample steel (30Mn-3Si-3Al) during equal channel angular pressing (ECAP), we carried out a comparative study on microstructures and the mechanical properties of the original state, the one pass pressing state, the ECAP1P+850℃×1h/A.C state and the ECAP1P+1000℃×1h/A.C state. The results of the experiment reveal that: during the deformation, because of the large amount of obstruction of mutual deformation resistance forces and dislocations of deformation twins in the deformation area, the TWIP steel showed a high degree of work harding for processing. After the air-cooling treatment of ECAP1P+1000℃×1h, the plasticity had been improved compared to the original state under the same strength. At the same time, the growing of grains had increased the length of shear channel of dislocation to the direction of the area of twins, and strengthened the storage ability of dislocation, thus showed an even higher degree of plasticity and the work harding ability during processing. After the air-cooling treatment of ECAP1P+850℃×1h, because the small grain increase the resistance of the dislocation, so the work harding ability had been improved.