【摘要】 针对高锰钢高加工硬化特性导致工业大压下率冷轧难以进行的现状，基于工业可行冷轧压下率(30%)对高锰TWIP钢进行冷轧，随后对其进行750和900℃退火保温不同时间的处理，获得不同比例(0%～100%)细晶镶嵌于粗晶基体中的单相奥氏体异质结构，分析了不同退火工艺下试验钢的再结晶形核机制。结果表明：在750℃退火保温300 s后，试验钢的组织主要由变形奥氏体和粗晶奥氏体构成，随着保温时间延长到1800 s,变形奥氏体逐渐通过亚晶合并形核的方式发生再结晶；在900℃退火保温300 s时，晶界形核占据主导地位，而保温时间延长到1800 s后，组织逐渐转变为等轴晶粒；其中，在900℃退火保温300 s后，试验钢得到了再结晶体积分数为30%的异质结构组织，在形变过程中通过位错塞积与孪晶诱导塑性(TWIP)效应协同作用，实现高强度与高塑性的优异匹配，其屈服强度与抗拉强度分别为611.1和915.6 MPa,同时保持52.5%的伸长率，强塑积达到48 GPa·%。更多还原

【Abstract】 In response to the difficulty of industrial cold rolling with high reduction rates caused by the high work hardening characteristics of high-manganese steel, cold rolling treatment with a feasible industrial cold rolling reduction rate(30%) was carried out on high-manganese TWIP steel. Subsequently, it was annealed at 750 ℃ and 900 ℃ for different time to obtain a single-phase austenite heterogeneous structure where different proportions(0%-100%) of fine grains were embedded in a coarse grain matrix. The recrystallization nucleation mechanism of the experimental steel under different annealing processes was analyzed. The results show that after annealing at 750 ℃ for 300 s, the microstructure of the experimental steel is mainly composed of deformed austenite and coarse-grained austenite. As the holding time increases to 1800 s, the deformed austenite gradually undergoes recrystallization through subgrain coalescence and nucleation. When annealed at 900 ℃ for 300 s, grain boundary nucleation dominates, while after the holding time increases to 1800 s, the microstructure gradually transforms into equiaxed grains. Among them, after annealing at 900 ℃ for 300 s, the experimental steel obtains a heterogeneous structure with a recrystallization volume fraction of 30%. During the deformation, the synergistic effect of dislocation pile-up and twin-induced plasticity(TWIP) is achieved, enabling an excellent match between high strength and high plasticity: the yield strength and tensile strength are 611.1 and 915.6 MPa, respectively, while maintaining an elongation of 52.5%, and the product of strength and elongation reaches 48 GPa·%.更多还原