应变强化对022Cr17Ni12Mo2奥氏体不锈钢显微组织和力学行为的影响

采用电液伺服万能试验机、X射线衍射仪、金相显微镜和透射电子显微镜，研究了应变强化对022Cr17Ni12Mo2奥氏体不锈钢微观组织和力学行为的影响。结果表明：前期预应变强化过程中，材料没有发生相变，形变孪晶数量的增加使材料的屈服强度和硬度得到大幅提高，但塑性有所降低，发生形变孪晶诱发强度效应。随着预应变量的增大，应变强化能力减弱，瞬变应变有所降低，位错的滑移模式发生转变，从单系滑移和平面滑移向多系滑移和交滑移转变。

Effects of Strain-strengthening on Microstructure and Mechanics Behavior of 022Cr17Ni12Mo2 Austenitic Stainless Steel

The effects of strain-strengthening on microstructure and mechanics behavior of 022Cr17Ni12Mo2 austenitic stainless steel were investigated by universal testing machine, X-ray diffraction, optical microscopy, and transmission electron microscopy. The results show that there is no phase transformation during the early stage of pre-strain strengthening. With the increase of deformation twins, the cold deformation can enhance the strength and hardness significantly, whereas the ductility of the steel is decreased. The deformation twinning induced strength effects are occurred. Meanwhile, the strain-strengthening ability of the strengthened steel and the transient strain are weakened with increase of the pre-strain. The appearance of deformation twins makes the change of dislocation slip mode, which transforms from single-slip and planar-slip to multiple-slip and cross-slip.