采用热力学计算以及XRD分析技术对18Mn-Si系TWIP钢的层错能进行了研究。结果表明,18Mn-Si系TWIP钢在淬火状态下为全奥氏体组织,拉伸变形以后出现变形孪晶和α马氏体相;该钢种的层错几率和层错能分别为2.6×10-3、17.3 mJ/m2,说明其在拉伸应力作用下将同时发生TWIP效应和TRIP效应,该结论与实验结果相吻合;对于18Mn-Si系TWIP钢而言,其在298 K条件下层错能(SFE)和层错几率(Psf)存在如下关系,即,SFE(298 K)=4.498×10-2/Psf。 The stacking fault energy of 18Mn-Si TWIP steel has been studied by thermodynamic calculation and XRD analysis. The results show that the 18Mn-Si TWIP steels are all austenite in the quenched state, and the deformed twins and α-martensite phases appear after tensile deformation. The stacking fault probability and stacking fault energy of the steel are 2.6 × 10-3, 17.3 mJ / m2, indicating that TWIP effect and TRIP effect will occur simultaneously under the tensile stress. The conclusion is consistent with the experimental results. For 18Mn-Si TWIP steel, under the condition of 298 K The relationship between the fault energy (SFE) and the stacking fault probability (Psf) is as follows: SFE (298 K) = 4.498 × 10 -2 / Psf.